[tamcap]

Many airports (in the US, at least) make much more money from parking fees than everything else. On top of that, at least some operate their retail in a royalties model too (ie 20% of all sales goes to the airport, before any costs).

Thus, there is very little incentive to keep you in the airport less, and multiple incentives to keep you there longer.

[standardUser]

That's what makes the 2-hour early 'rule' so egregious. Manipulating passengers to sit around in a Disneyland-priced mall because of the 1 in 5 chance the TSA screwed up their staffing that day.

[rossriley]

I think Singapore has a pretty good experience worked out now, the immigration is automated just with an iris scan.

Additionally moving security to the gate rather than having a single security point for all flights also makes the wait here shorter and more importantly predictable.

If I'm just taking a cabin bag I always arrive 35-40 minutes before a flight and have had no trouble with time, normally enough time to grab a coffee too before boarding.