There are two common clutch failure modes: disc wear and throwout bearing failure. Sometimes the pressure plate fails, but that's only when it's abused by major slippage and overheating, which causes the springs to lose their temper.
Disc wear causes less "grab". The clutch is self-adjusting, so you won't really know it's gone until it's gone. Frankly, if you're a good driver, and most of your miles are on the highway, this probably won't happen until 150-200k. Or longer. Just remember: the clutch is either up or down; not in between.
Throwout bearing failure seems to happen more often. This is characterized by a grinding noise and feel (in the clutch pedal) when the clutch is depressed. Happened in my e36 at 145k. (The disc looked fantastic in that car at the time.) BMWs seem to like to toast their throwout bearings, but you can help by not sitting with the clutch down for any longer than you need to. Be sure to put it into neutral at red lights and keep your friggin foot away from the clutch pedal.
We could discuss the pilot bearing, but since I've never seen one fail, we'll save it for another time.
Hope this helps.