I don't think Lionhead has made many games that were bad, but it also hasn't had any 'OMG, this is great' games. Fable almost always leaving me wanting, and thinking it could have been done a lot better, but at the same time it's a decent enough series where I do follow it.
See, what I think a lot of people don't get is that even the best games get boring after a while, as a gamer you need to play a lot of differant stuff. When people respond to your criticism by going "well why do you play it?" the answer is typically "because it's what is out there that I haven't played yet". Just because you say a game is average, or even sub-par, doesn't mean that it has no redeeming qualities at all, it's a comparitive thing. Nobody holds a gun to your head and forces you to play anything, but at the same time you do want the games you play to be better.
That said Lionhead's games are ones I am frequently critical of, but they are usually "decent" as opposed to "really good" or "great" to me, and usually I play them in lieu of other, worse alternatives, as opposed to nessicarly getting all psyched up for
"OMG, another Fable" or something like that.
Peter keeps trying, and I can respect that though, and I really hope he does make that "great game" some day. Both for him, and also for me so I can play it.
Of course also understand that my definition of what makes a great game is differant from a lot of people. At 35 I'm an old fogey given the rate at which the industry moves. While not that young a guy Peter Molyneux has been a name fairly recently. To me I tend to prefer the style of guys like Richard Garriot back in the day. I'd love to see something like Ultima IV, V, or VI done with modern technology. Not so much remakes of those games, but that style of gaming if you catch what I mean. Ultima, Might And Magic, Wizardry, those are the defining games for me as an RPG player, and really the guys who are around now just don't think that way for making games.