Often times I have to pass up open seats because passengers have loaded their luggage sideways, effectively allowing for 2 rollaboards per overhead bin versus three. I always load my rollaboard wheels-first, and, as far as I can tell, it's standard size.

Are WN's bins simply not deep enough for most rollaboards? On AA, the FAs typically request passengers to load wheels-first, which saves a lot of space.

Thanks for any insight.