You'll never have to pay for a cab (or take a train if you don't want to) to the airport for work...but you still would benefit from easy enough transit to the airport. For instance (thankfully I very rarely travel), I am pretty close to ohare (though I prefer MDW) and a taxi can get me there pretty quick for an early morning flight....but if I was frequently getting off a plane at 5:00, it would be a gigantic pain in the ass. It is way faster to take the train to my cross street and grab a cab there because being near the airport at rush hour sucks. Living somewhere that is an easier drive to the airport OR an easier direct train ride would make my life far easier if I was travelling every week.
Until more and more planes have internet
It's unreliable - you can always say it was not working.