A few thoughts:
Over the years of hiring I have asked more than one escort how he got started in the business. The majority found out that somebody they knew was in the business and decided to give it a try based on what their friend/acquaintance told them -- the chance to make tax free money doing something they enjoyed was too intriguing to pass up. A minority accepted a proposition to have sex for money (either because they needed it or out of curiosity or a sense of adventure) and then subsequently found out that it was in fact a profession and joined the ranks.
It is, to me, surprising, how many escorts are also on Scruff and/or Grindr. I have the impression that a lot of them REALLY enjoy sex, at least some to the point of a sex addiction. (I realize some of the profiles may just be stolen pics.) The few times I've been rimmed by an escort, it was always initiated by the escort and totally obvious he was having a great time, indeed, I wasn't sure he was going to stop, to my great pleasure. Based on how well many of them kiss, which is a big thing for me, I'd say they enjoy that a lot, too.
From my conversations with escorts, money seemed to be one factor for all of them.
More than one talked about regulars who only want company or cuddling and rarely sex.