Size + Time... enemies in service rankings.

People forget slowly and the more chances they have to use your business, the more chance there is for it to go wrong.

UA could improve a lot, but at the same time, people want everything for nothing [or as little as possible]. Personally I think UA or another airline would do well to return some of the features that have been a-la-carted and focus on delivering a decent all around experience rather than ending up on the dime to dime comparisons. People would like to eat on a 5 hour flight. People still check. Yet even knowing there's a savings by not paying for these things, people get upset when they have too.