No one expects the best loot on a plate. People expect some actual variety and atleast some progression in a multi-hour session.
In Diablo II, there were constant drops and you always were making a choice about which piece of gear suited you the best at that moment in time.
In Diablo III, you get a drop for a specific item slot after 4 hours (even in low difficulties) thats marginally better, and you use it because there is no alternative.
In Diablo II, items may have lower base stats but improve a skill. You then have to make a decision about whether or not that skill is worth the tradeoff.
In Diablo III, items with lower base stats nerf all of your skills, almost always leading to there being no sense of choice because item A is plain better than item B.
In Diablo II, the drop rate was high enough that you always felt capable of continuing. Those who explored every nook and cranny were rewarded with being slightly overpowered.
In Diablo III, the drop rate is so low that you frequently will find yourself pathetic compared to the enemies, and be nearly forced to look at the auction house.
This next one is a personal issue of mine:
In Diablo II, you get a drop that's much better and you think "Wow, this is amazing!". You always feel powerful.
In Diablo III, you had to use the Auction House to continue, and have to filter through all of the vastly better items at your level to settle on one that's reasonably priced at that point in time. This feels the equivelant of if Diablo II displayed a list of better gear next to every drop you pick up, to constantly remind you that your gear sucks in the grand scheme of things. You always feel weaker than others.
