<p>Well, the calculation involved in keeping that guy is complicated. Sounds like some of the factors involve:</p>
<p>Strict business:
1.) How much does he cost by scaring customers?
2.) How much does he cost by being inept at his job?
3.) How much does his presence decrease his girlfriend’s productivity by being a distraction?
4.) How much would his absence upset his girlfriend and decrease her productivity?
5.) Would she leave if he were dismissed, and what’s the cost of replacing her and training her replacement? Would her replacement be better or worse at her job?
6.) Is this a long term investment? Might either of them improve considerably in the future?</p>
<p>In a non-business sense:
1.) “I know he’s a horrible worker, but I’m trying to be nice to him.”
2.) “I know he’s a horrible worker, but I’m trying to be nice to his girlfriend.”
3.) “Firing people is just too annoying and stressful to be worth it.”</p>