A couple years ago I "wasn't feeling well" but was on my way to spend a weekend with my wife who I hadn't seen in a month so I was going to push through.

I passed out twice at the airport (first while talking to a friend.... Second when they had gone to their office to grab me something to snack on since I hadn't had anything to eat. Airport EMS cleared me* medically and could have made the original flight but I was told by my friend, a lead, and basically every UA employee not actively working a flight that they though it would be a terrible idea for me to go as booked.

They proactively got me space on a later flight up front with a very clear "if you aren't feeling 100% up to it do not feel like you have to go and we will get your ticket refunded" as well an offer to get my wife to me instead of the other way around... Just needed to know what flight to book. After a few hours of rest in the airport and some food was feeling much better and the rest is history but that is one of 3 or 4 specific reasons why United still gets 100% of my flying spend.

One of a handful of very specific and personal ways UA has gone far above and beyond for me

*- While EMS was checking me out there was a 360-degree wall of UA employees around me "Does he work here?" "No...he just flys us...a lot" :-)