I haven't been to the best clubs, so my experiences probably haven't been the best they could be.
Anyway, I enjoy some good dancing every now and then, and clubs usually fit the bill. I'm a little peeved that most of the clubs I've been to play only top 40 music and terrible remixes of said music. The DJs are often pretty bad and try to combine new songs with old favorites, and it doesn't go well. I don't really want to hear dance-pop beats added to Michael Jackson songs and whatnot. I also don't want to dance to a dance-pop version of Don't Stop Believin'. Some of the shit out there is so bad I just stop dancing and shake my head. I really need to find some new places that play actual dance music and not just "pop music that's dance-able."
The crowds can range from good to terrible. I can't stand it when I'm trying to have a good time dancing with friends/girlfriend but then I stop and realize that there are tons of people standing on or around the dance floor not doing anything at all (and just watching the people who are dancing). Kills the vibe. In general, it has been hard for me to find good, lasting vibes in clubs; a lot of the people who go are posers who don't actually want to dance; they just get an alcoholic beverage and watch everyone else, acting as if they're actually participating in the scene. I hate it.
When I dance, I like to be a little wild and creative. Nothing crazy, but I'm not one to just bob up and down to a song unless I don't really care for it. I feel like I'm in the minority though, since a lot of other folks are content with bobbing, while I'm there trying to vary it up a bit. This leads into another issue I have with the music: that it's inherently bob-friendly. DJs often play popular music and keep basically the same beat going through several songs, and it's annoying. Obviously when you keep hearing the same shit you want to start bobbing because you're tired of trying to do anything more interesting with the same beats going over and over again.
Also, creative and wild dancing is basically foreign to everyone. My brother is an amusing dancer and he always has a blast, but several times I've seen people take videos of him with their camera phones. He just gets really into it, and the idea that quirky, wild, and creative dance efforts are looked at oddly is disheartening. Someone has to break from the head-bobbing mold of the club-going majority! I'm not like my brother but I still put effort into my dancing and there is never much appreciation for it. This goes back to the point I made about "vibes." It's just not fun when there's no energy in the crowd and everyone's content with the bear minimum.
I don't need to drink alcohol to loosen up, so I appreciate being able to enter a club and have a good time dancing off the bat. But most people aren't willing to do much until they've have a few drinks since they're incapable of being fun without being dis-inhibited. This makes it so that clubs aren't actually enjoyable until at least 11pm if not midnight. Dance floors take forever to get any action, because no one is on the same page. Obviously I don't want to be the sole dancer on the floor because I'll feel silly, so I wait until others get started. But everyone thinks like this, so it takes a lot of waiting and alcohol consumption for things to get to the fun part. There are times that my friends and I have tried to get things going, but the attempts usually fail.
The women at clubs are typically fine, but it seems that the guy population is dominated by scumbags, bros, and posers. There's always some drunk asshole getting into a fight, at the cheap-cover clubs anyway. But in general the people at clubs are just awful in terms of any sort of "club etiquette." They spill drinks on the floor (making it a slippery mess), they move through a crowded dance floor when they could easily go around it (making dancing difficult since you have to clear the way for them; this is especially frustrating when I want to dance intimately with my girlfriend); they get in the middle of the dance floor only to stand still and text their friends the whole time, etc. People always find ways to destroy the fun, with just these "little things" that they do.
In some places, the music is too fucking loud. I know that going to a club isn't about hanging out and talking with friends (necessarily), but it would be nice to actually be able to communicate with others when the need arises without having to yell into their ear. I know loudness allows people to get drowned in the sound of the music, but there's a point where it's loud enough without completely destroying communications between me and my friends, me and the bartender, or me and anyone else.
Drinks are overly expensive and are nothing to call home about. Sometimes they're even watered down. This is why I usually try to skip them; don't need to fall for the money sink.
In the end, I don't think highly of the club scene. It's probably because I haven't exposed myself to the proper venues, of course. Thus far there are many issues I have with the scene, and they mostly involve bad music and bad people, with a combination of other factors.