Yes, Stephen Colbert has left The Colbert Report. It's a deeply sad moment for all of us who love great satire and funny late-night talk shows.

But he actually might not be the best late-night host stepping down from his job this week. Craig Ferguson steps down as host of CBS's The Late Late Show with Craig Ferguson tonight, and that might have me even sadder than Colbert's final episode.

The two have been the best late-night hosts out there for roughly five years now, trading the title back and forth, seemingly with every new week. (John Oliver might challenge the two with his HBO show, but that's such a different animal from a nightly talk show that I'd hesitate to name him the victor.) Sure, Ferguson has moved on to the game show Celebrity Name Game, but it's not the same.

As host of the Late Late Show, Ferguson brought an easygoing manner and appreciation of lunacy to the role of "guy who's meant to lull you to sleep." His series had an appealing, timeless quality that felt as if it were a holdover from the glory days of late-night TV. That he struggled so mightily against inferior competition on NBC makes it all the more frustrating that he's stepping down after a decade at the show's helm.

Yes, with Colbert in David Letterman's chair and James Corden in Ferguson's, CBS could have a couple of solid shows. But neither will be Ferguson's show. Here are five reasons you should be sadder than you are that his run ends tonight.

1) He was the best damn interviewer in late night

Ferguson had his faults here and there — particularly his over-the-top horndog routine he broke out when attractive actresses visited — but he consistently refused to follow the script and simply promote whatever pop-cultural artifact a celebrity was there to promote. That made him a rare commodity in an increasingly homogenized late-night landscape, where interviews feel rehearsed to death. (This is especially true of Jimmy Fallon's Tonight Show, which still feels as if Fallon is trying really hard not to provoke any emotion whatsoever in his guests.)

Not every guest was a great fit with Ferguson, but the ones that he clicked with — like, say, actress Kristen Bell — returned again and again, because he had a way of making stars seem not just like hustlers promoting product, but actual human beings who had interests outside of their work. He was the only late-night host who could, somehow, credibly turn over an entire hour to talking to Archbishop Desmond Tutu and make it riveting TV.

Colbert is a great interviewer, too, particularly when you factor in that he has to interview in character. But Ferguson was a real treasure, and it's too bad we won't get his weird, nightly riffs on the lives of the stars anymore.

2) He was unapologetically silly

A robot co-host. Puppets. A dancing horse named Secretariat. A tribute to Doctor Who in song (that, sadly, never made it to air, due to music rights issues). Ferguson wasn't afraid to be goofy, geeky, or even outright stupid if it meant getting the kind of unvarnished laughter that's really only possible when you're dead tired and stumble upon something strange on TV.

Ferguson is Scottish, and there's a thick sense of British sketch comedy hanging over the show, with its weird recurring bits and its numerous running jokes. Even when he was beating one of these jokes into the ground, it was clear that he was doing so just so it would swing back around to being funny again in a few weeks' time.

3) He experimented with form

Ferguson's show took road trips to other countries that turned into impromptu travelogues. It would sometimes open with a puppet directly in front of the camera, or it would be fine doing a show during a power outage. Ferguson's unflappability made literally anything that happened on the stage he stood on seem like it was meant to happen, even if it was self-evidently disastrous.

The late-night talk show has been in need of reinvention for decades now. Ferguson didn't quite break the mold, but he certainly pushed as hard as he could against the edges of it. It was a tricky balancing act that he handled beautifully.

4) The monologues, the monologues, the monologues

I had friends who kept the Late Late Show on their DVR record list just for Ferguson's monologues, which were frequently brilliant, beautiful, and perfect pieces of comedic writing. They almost always centered on a single topic, rather than turning into a series of disconnected jokes about the day's events, and in their finest moments, they flew from comedic peaks to genuine, moving valleys.

He also wasn't afraid of opening up about serious subjects. Look above to see how beautifully written and constructed perhaps his most famous monologue — in which he pleads with people not to make fun of Britney Spears and opens up about his own hard-won sobriety — is, how wonderfully it balances your expectations of the form (jokes!) against the very serious thing he's trying to say. It's wonderful, and it's the sort of thing that might have happened on any given night on his show.

5) Ferguson loved anarchy

This, in a way, is just a summation of all of the above points, but in the show's finest years (roughly from 2007 through 2013), it was deeply subversive because it essentially suggested that while the usual talk-show templates and formulae applied, they were mostly excuses to try to break the rules as much as possible. Ferguson stuck to the typical talk-show script — monologue, followed by sketch, followed by first guest, followed by second guest, followed by musical guest or comedian — but at all times, there was a sense that the bottom could fall out of the show, and it might become something else entirely.

The adjective that might best apply to the series was restless. Ferguson always seemed like he was looking for something else to ask about, some other joke to crack, some other conversation to have. The show's focus roved everywhere, but that was because the attentions of the man at its center did as well.

That restlessness may have ultimately been why he left the show. Ferguson claims he's leaving of his own volition, rather than because CBS wants to clean house. And normally, I wouldn't buy that from a man who went from a late-night talk show to hosting a syndicated game show. But that restless quality has shown up in this year's episodes, as he's seemed ready to be done, ready to move on. The very thing that made his show so exciting is quite likely what ended it. But it also meant we got a near-perfect 10 years of late-night TV, and that, in the end, was worth it.