I just discovered that JetBlue has a list of international check-in times on their website, by which they mean at what time people should arrive at the airport for departures to various international destinations:

When traveling from any of our international destinations to the United States, we suggest you arrive at the airport 2-3 hours before your scheduled departure. Recommended check-in times for each international destination are listed below. Please note: the recommended check-in time for travel to Cuba is 4 hours.

[…]

International location/airport Check-in time*

Aruba (AUA) 3 hours

Bermuda (BDA) 2 1/2 hours

Bogota (BOG) 4 hours

Camagüey (CMW) 4 hours

Cancun (CUN) 3 hours

[…]

*Check-in Time refers to the hours before scheduled departure Customers should arrive at the airport

Why do these times differ between different destinations? For which step between “arriving at the airport” and “boarding the flight” does a passenger to Bogotá need longer than a passenger to Bermuda? (I just picked a random pair where these times differ, I’m more interested in the general reason why these times are not all the same.) Or is it that their luggage needs longer? How are these times calculated?

JetBlue calls these times recommended: What happens if I arrive at the airport later? Might they deny taking my suitcase? Will they deny me boarding? What factors do influence whether arriving later is ok or a bad idea (I guess that’s related to the questions in the first paragraph.)?