Brendan Rodgers accepted full responsibility for Liverpool's dire performance at Hull City when he reappeared on Monday. "If there's anyone to blame, blame me," he said of the "painful" 3-1 defeat. The delicate issue of responsibility for the strength of Liverpool's squad, however, saw Rodgers at his diplomatic best. With good reason.

The Liverpool manager invited scrutiny at the KC Stadium by claiming his squad could not cope with the loss of two key players in Daniel Sturridge and Philippe Coutinho. Given what a side with Champions League aspirations had just served up against Hull, who had scored only four league goals at home to their name before kick-off, it was impossible to disagree. It was also difficult to accept.

Liverpool signed eight players in the summer, two on loan, for almost £50m but only one – the goalkeeper Simon Mignolet – has truly established himself in the first team. The rest may have improved the depth of the squad, a task Rodgers and the owner, Fenway Sports Group, agreed on for the summer, and may yet enhance Liverpool's future.

Overall results in 2013 and a consistent place in the top four this season demonstrate that FSG's strategy of acquiring young potential and the occasional gem such as Coutinho has its merits. The intended path towards a Champions League return has been clear since Rodgers arrived and a transfer "committee" was set up but Sunday's display, and the manager's analysis, suggest the transfer policy has not maximised the prospect of a top-four finish this term.

Rodgers wanted not only depth this summer but proven first-team talent, a request he recently repeated in advance of the January transfer window. The cost of being outside the European elite hit home as Henrikh Mkhitaryan chose Borussia Dortmund over Anfield, Diego Costa secured a better contract from Atlético Madrid and another top target, Willian, opted for the periphery at Chelsea.

Then, having pursued attacking quality all summer, the club spent around £24m on two more central defenders, £18m Mamadou Sakho – the "marquee signing", according to the managing director, Ian Ayre – and £7m Tiago Ilori, having secured Kolo Touré on a free. Ilori has yet to appear for the first team and, when Rodgers dropped Daniel Agger at Hull, he preferred Touré and to switch Martin Skrtel's position instead of a straight swap for the expensive France international.

Another £13m was spent on Iago Aspas and Luis Alberto, more potential and not an obvious improvement on players they effectively replaced in the Liverpool squad, Fabio Borini and Suso. Clearly successes such as Coutinho and Sturridge are difficult to land without the attraction of Champions League football and two creative losses are bound to impact on the performance level. But Liverpool's approach appears scattergun in comparison with, say, Southampton's £36m spend on three players who instantly improved the spine of their first team – Victor Wanyama, Pablo Osvaldo and Dejan Lovren.

"It was about the players who were affordable and available," said Rodgers on Monday. "We tried to get a host of players in and get the types who could improve us. At the same time we knew we had some who were going and had to replace the likes of Jonjo Shelvey, so we needed to bring in ones who would give us cover. We all recognise we wanted to get in one or two more starters, which didn't materialise. A lot of work went into it. What is the case is we are not in a position to spend money for the sake of it. We are trying to build for the future with a sense of the present, which is to strengthen where we can. You can only do that if you can bring in players who will enhance the team, or you just stockpile players."

As for Sunday's comment on the strength of Liverpool's squad, the manager elaborated: "The thing for me is trying to maximise the players we have got. It's more about putting it in context when you compare squads, not on money spent. For example look at Chelsea, and it's hard to agree on what is their A team and their B team, probably with Man City too. The point was made in terms of our expectations, which are the same as those clubs, but we don't have that type of depth. There's no hiding from the fact we spent money to get players in and now they will be getting the chance to perform."

Transfer strategy cannot solely be blamed for Sunday's performance when talents such as Victor Moses and Raheem Sterling wasted their opportunities to impress. But Rodgers' selections, and the contrast between the type of player he wanted to buy and received, suggest a marked difference of opinion with others on Liverpool's transfer "committee".

"Listen, I am privileged to be here and I know the conditions that I have to work in," he said on that subject. "We know where we are at as a club. We are trying to grow something here and develop it. We are not going to be in a position to improve it all ways straight away. But there is no frustration. I am privileged to work here. The only frustration comes after performances and results like against Hull. I will work within the constraints of the club and do the job the best that I can."