The amount of comp you get for small shit (e.g. broken light, no recline, no IFE/wifi) is largely dependent on your status. A no-status member might maybe get 500 miles on United, where as a Global Service might get up to 10K+ (depending on severity)
They will often send you emails where you have to complete a form/survey to get the offer. I usually request the comp. You can call in or email - if you're 1K / GS, there are dedicated email addresses with 24 hr response
