For various reasons, this is actually my second working persona - Amy first appeared only in December last year and I really didn't want to go on Adultwork as I hated the overall look of the site, all the bareback ads and so on (I think Evie said something similar on another thread). However, I had just decided to go full-time and pack in my day job so while I was waiting for my personal site to be finished, I put up a profile - I got the usual flurry as the 'New Member Alert' went out, and also a few good jobs through the reverse booking system, but all in all, Adultwork is not a particularly busy source of work for me and many more clients find me through my website. Having said that, it does often feature highly in my site traffic, so I may well be selling it a bit short!
I can honestly say that I get comparatively busier as every month goes by; this isn't the most prosperous time of year for any of us, but I still often have a full diary, and not just regular clients - I see lots of new clients too. I think there is possibly a brief dip when the 'novelty' of being new wears off and the regular custom hasn't quite fully built up, but I can't say I noticed it, perhaps because I don't have much local competition and I am under no illusions as to how much that helps me. I value my good reputation and work hard at it; I keep my advertising timely and relevant, maintain myself, my home and my service and go out of my way to be consistant - I am not afraid to turn bookings down and often do if I know I am not up to it.
To answer the OP, I think the 'rumour' is both true and untrue, and depends entirely on your approach to your business. It is definitely not true in my case, but for ladies who just want to make a lot of money quickly and do not need to think of escorting as a long-term proposition, there are certainly ways of doing just that and then packing it all in just as quickly (and hopefully before you burn out in the process).