Pride is the glaring example. Most other songs that I think suck live, I don't find to be much better in the studio (for example, I find Miracle Drug a letdown live, but it's hardly a classic studio song either). On the other hand, the studio version of Pride is a U2 classic, and I think it's a terrible shame that 1. U2 have almost always failed to play it well live and 2. that it is bordering on overtaking I Will Follow as the band's most played live song despite how dreadful it is on stage. I largely blame Edge in the eighties and nineties, as the guitar just lacks the chiming and resonance and tone it has in the studio, and from Popmart onwards I blame Bono simply not being able to hit the chorus. On Vertigo, Edge seemed to actually get the guitar right and I'd say Pride was the best it has been since the mid-eighties. I can only name two studio performances that are superior to the studio version: 31 August 1984, Wellington and the March 1987 appearance on the Old Grey Whistle Test TV show. I also find the 30 December 1989, Dublin performance at least enjoyable, but not of the quality of the studio version.
Pretty much every other song played live that I can think of has been bettered its studio version. Well, I suppose songs like So Cruel and IGWSHA and WUDM weren't better live, but either they were never properly done in full to have a basis for comparison, or in IGWSHA's case, they had one full performance that was unremarkable and then the band hastily gave up and gave it the incomplete live treatment that So Cruel and WUDM had.
Oh, and some songs NOWADAYS are much weaker than their studio version, e.g. WOWY and SBS, but in their prime were absolute U2 live classics. Very little can top WOWY 1987-1992, or the Fuck The Revolution performance of SBS. But WOWY never should have been played since 1993. It's so lacklustre now, especially when Bono doesn't add Shine Like Stars.