We recommend against using them but we know that integrators do. High humidity environments can corrode the exposed ends causing a short. That is one of the biggest reasons I know of.

I haven't terminated a lot of CAT cable, but the small numbers that I have done was a PIA. When a client complains about the price in a proposal, you should hand them a foot of CAT cable offering a discount if they can terminate both ends in 10 minutes then and it has to work. Then tell them you have to do this 50 to 100 times in your project.