Football has a habit of reminding us of our mortality. The transition from hot young prospect to experienced old hand takes place in the length of time it takes most of us to blunder from A-levels into something approaching a regular job. A life in football is real life speeded up, and that is truer even of great sides than great players: they rise, they flicker, they shine, they win things, they fade, the descent seeming usually more rapid than the ascent and generating far less historical interest.

The thought of decline seemed to haunt Pep Guardiola. Even as his side produced some of the finest football the world has known, even as it controlled games and destroyed teams, in three years landing an unprecedented haul of trophies, he seemed unable to enjoy it, worrying always about what came next, about sustaining that level of brilliance, his anxiety graphed in the retreat of his hairline.

"The third year is fatal," said the great – and irascibly peripatetic – Hungarian coach Bela Guttmann and there does seem to be a general truth that, particularly with hard-pressing sides, three years is the maximum lifespan of a great side. But it is just a general truth; in each case there are specific causes.

Sic transit gloria mundi

One of the biggest problems, of course, is that players get old. That was what ended up doing for the great Real Madrid side that won five European Cups in a row between 1956 and 1960 (avoiding Guttmann's Three-Year Rule with constant changes of manager). Although they, thanks largely to the wealth that enabled them to buy the cream of Europe at a time when very few clubs did that, won five straight league titles between 1961 and 1965 (and added the 1966 European Cup as well), it's striking that both Ferenc Puskas and Alfredo Di Stéfano played in the 1964 European Cup final against Helenio Herrera's Internazionale at the age of 37, while José Santamaría was 34 and Paco Gento 31.

Age did for the Leeds that Don Revie left in 1974, for Brian Clough and then Jimmy Armfield, even for Bill Shankly's first Liverpool, although he was able to construct another great side before his retirement. The management of transition was what allowed Bob Paisley, Alex Ferguson and Valeriy Lobanovskyi such lengthy careers and such sustained at one club. But it wasn't only age that did for Real; by 1964 Real weren't just an old side, they were an outmoded side. Tactical history had moved on and the man-marking of Inter stifled Gento and Puskas in particular.

Events, dear boy, events

Sometimes, of course, outside events intervene. The Dynamo Kyiv side that won three successive Soviet championships under Viktor Maslov came about because he was forced to promote players from the youth side with several of his first team squad being away at the 1966 World Cup (the Soviet authorities being two cussed to pause the league campaign during the tournament). He ended up being sacked – left at a Moscow Metro station to make his own way back to Kiev – because when he had to do the same during the 1970 World Cup, those coming through the youth ranks weren't anywhere near as gifted as the generation of 1966 had been. More tragically, the great Crvena Zvezda team of 1991 was broken up before its time because of the civil war.

Or take the Liverpool of the early 90s. The introduction of the backpass law meant they would have had to change their approach given returning the ball to the goalkeeper was central to the way they controlled games – as it had been to Nottingham Forest, who played a similar style and were relegated in the first season after the law came in partly because the ageing Brian Clough was unable to readjust. The new environment of the Premier League created different commercial demands and possibilities and there can be little doubt that Liverpool soon fell behind Manchester United in that regard. But had Hillsborough not happened, had the club not been shaken by grief and anger, had an exhausted Kenny Dalglish not resigned, Liverpool might have been better prepared to meet those challenges.

So events and tragedies can bring a great side to an end – in a horribly direct way in the cases of Torino at Superga and Manchester United at Munich. But again and again, particularly with teams who pursued a clear and radical philosophy, what brought them down was neither age nor circumstance but an odd sense of being too much themselves.

A negative self-immolation

By April 1967, Herrera's Inter were four points clear of Juventus and had beaten Real Madrid in the European Cup quarter-final, but abruptly, things fell apart. Two 1-1 draws against CSKA Sofia in the semi-final forced them to a play-off – handily held in Bologna after they promised the Bulgarians a three-quarter share of the gate receipts – and although they won that 1-0, it was as though all the insecurities, all the doubts that had led them to their defensive approach, their philosophy of focusing on minimising the opposition's strengths rather than maximising their own, rushed suddenly to the surface.

They drew against Lazio and Cagliari, and lost 1-0 to Juventus, reducing their lead at the top to two points. They drew against Napoli, but Juve were held at Mantova. They drew again, at home to Fiorentina, and this time Juve closed the gap, beating Lanerossi Vicenza. With two matches of their season remaining – the European Cup final against Celtic in Lisbon, and a league match away to Mantova – two wins would have completed another double. The momentum, though, was against them.

There was talk of boardroom unrest, of Herrera being courted by Real Madrid, Sandro Mazzola suffered a bout of flu then Luis Suárez went down with a thigh injury. In the ritiro, the retreat where Inter's players were corralled away from their families and other distractions, the tension got worse and worse. "The pressure just kept building up; there was no escape, nowhere to turn," said the right-back Tarcisio Burgnich. "I think that certainly played a big part in our collapse, both in the league and in the final."

It was even worse in Lisbon, where Inter prepared for the final in a seafront hotel, half an hour from the city. "From the minute our bus drove through the gates of the hotel to the moment we left for the stadium three days later we did not see a single human being apart from the coaches and the hotel staff," Burgnich said. "A normal person would have gone crazy in those circumstances. After many years we were somewhat used to it, but by that stage, even we had reached our breaking point. We felt the weight of the world on our shoulders and there was no outlet. None of us could sleep. I was lucky if I got three hours a night. All we did was obsess over the match and the Celtic players. [Giacinto] Facchetti and I, late at night, would stay up and listen to our skipper, Armando Picchi, vomiting from the tension in the next room. In fact, four guys threw up the morning of the game and another four in the dressing room before going out on the pitch. In that sense we had brought it upon ourselves."

As wave after wave of Celtic attack crashed upon them in the final, Inter were too exhausted, emotionally and mentally as much as physically, to respond and, having taken the lead with an early penalty, lost 2-1. On the final day of the league season, as Juventus beat Lazio, the goalkeeper Giuliano Sarti allowed a shot from Beniamino Di Giacomo – the former Inter forward – to slip under his body: Mantova won 1-0, and the scudetto was lost. The focus, discipline and caution that had once made them great eventually overwhelmed them.

Rotting fruit, dying flowers

It was a similar case of too much of the thing that made them great that undermined Europe's next great side. Celtic had proved that total attack could overcome total defence, something that served as a precursor to the arrival of Ajax and Total Football. It's often thought of as an attacking system, but it's perhaps best thought of as a proactive way of playing. As was shown by the 1972 and 1973 European Cup finals – both won against Italian sides practising a form of catenaccio, Ajax were perfectly capable of defending by retaining possession – and that was an Ajax side playing more relaxed football than they had under Rinus Michels.

Appalled by a defeat to Sparta Prague in the quarter-final of the European Cup in 1966-67, Michels set about rebuilding his defence, bringing in the combative libero Velibor Vasovic from Partizan. Vasovic insisted he added "toughness and discipline and a winning mentality" to the side. Aged only 31 but suffering from asthma, he retired after captaining Ajax to the 1971 European Cup – at the same time Michels left for Barcelona.

Vasovic was replaced at libero by the more attack-minded Horst Blankenburg, and Michels was succeeded by the avuncular Romanian Stefan Kovacs, who took the handbrake off. Ajax produced arguably their best – or at least most attacking – football in his first two seasons, but at some cost. "Kovacs was a good coach," the midfielder Gerrie Mühren said, "but he was too nice. Michels was more professional. He was very strict, with everyone on the same level. In the first year with Kovacs we played even better because we were good players who had been given freedom. But after that the discipline went and it was all over. We didn't have the same spirit. We could have been champions of Europe for ever if we'd stayed together."

Just as Inter had been too constrained, Ajax were too free. Put like that, coaching a side comes to seem like gardening: the fruit will be at its juiciest and sweetest, or the flower at its most fragrant, at the precise moment before it begins to rot. A coach's job then becomes almost to shield the plant from the sun, to delay maturation to prolong the flowering for as long as possible.

Oedipus at Camp Nou

What is fascinating about Pep Guardiola is that he seemed so aware of the dangers of Guttmann's Three-Year Rule. In that sense, his final season at Barcelona became like a Greek tragedy – the hero aware of his destiny yet unable to avert it; or even, like James Cole, the Bruce Willis character in Twelve Monkeys, creating the conditions in which his destiny could be fulfilled by his attempts to avert it. Guardiola had brought in Zlatan Ibrahimovic to offer a variety of attack, but was forced to offload him because Ibrahimovic's personality threatened to destabilise the squad just as, at Milan in the dog days of Arrigo Sacchi's reign, egos had begun to question the exhausting, repetitive methods employed to get results.

So he experimented with the back three. It seemed to be working last December when Barcelona won 3-1 at the Bernabéu, but even then there was a suspicion Guardiola had overcomplicated things, that the measures he had taken to avert his destiny were precisely those which ensured it came to pass. He was worried by teams sitting deep against Barça, worried that his team would become predictable, and so he devised a way of getting more players, Dani Alves in particular, higher up the pitch to try to outflank blanket defences. All that did, though, was to make Barça more predictable: it is easier to mark a player who starts high than one coming from deep.

It wasn't the sole cause of that odd flatness Barça demonstrated in the final minutes of the Champions League semi-final second leg against Chelsea, but it did explain why they never had players bursting at pace through the defensive lines: everybody was too near the box already – they couldn't build up enough pace already to be travelling at speed when they ran on to the ball.

By then, you wonder also whether Guardiola, clearly contemplating the end, was in the grip of a fatalistic idealism; that he was determined his team should have the most Barça-ish identity of all Barças, come what may, particularly in the moment at which his Barça faced its dissolution. His determination to play with fewer and fewer defenders – even, at times, to reinvert the pyramid – became almost the altruism Ernest Becker discussed in his re-reading of Freud. If, as Samuel Weber said, "the pursuit of meaning; the activity of construction, synthesis, unification ... all this indicates the struggle of the ego to establish and maintain an identity", then what better way, when facing the dissolution of the ego, to assert mastery than for the ego to dissolve itself by following to the ultimate the philosophy from which it derived meaning?

This was a theme that fascinated Joseph Conrad, and the deaths of Jim in Lord Jim or Axel Heyst in Victory pursue a similar logic. The most striking literary template, though, is provided by Oedipus. Not only did Oedipus, running away in an attempt to thwart the prophecy that he would kill his father and marry his mother end up preparing the ground for exactly that, but one reading of the Oedipus Complex has it that the child wishes to be rid of the father not because of desire for the mother but in order to remove the reminder of the "blind chance" (to use Darwin's phrase in his discussion of the issue) that has brought the ego into being. Becker's altruistic hero-ideal is a way for the ego to assert control at the end of life, the Oedipal longing to be rid of the father a way for it to do so at the beginning; for the ego to become, in Spinoza's formulation, causa sui.

Rather than just let his Barça wither away, rather than face the prospect of their philosophy being overcome, rather than risk the intervention of random events, Guardiola sought to stave off the entropic imperative by exaggerating what had made Barça great, by holding possession even longer, by getting even more men forward. It was failure, but at least it was failure on his terms.

And thus we see the great truth Duncan Hamilton saw in Peter Taylor after Nottingham Forest had retained the European Cup by beating Hamburg in Madrid in 1980, that for all sides, in the moment of their greatest triumph the seed of their destruction is already beginning to sprout. Glory comes as the beginning of the end.