[cheri1122]

They advertise for teams because it's to their advantage to have teams available for the long runs. They really don't care whether you would 'move up' to a larger truck, (if you earned enough money to do so), they care about covering all the loads they might get. Which means having more units signed on than are needed on any given day (some of which will be out of service).
I personally would think that turnover is a very bad (and costly) problem, but apparently, many carriers consider it preferable to doing what it takes to retain the good O/Os & drivers. And as long as there are newbies ready to jump in, they have no problem signing them on. Until the labor market changes, (which aint happening any time soon), the carriers have an almost endless supply of folks ready to sign on, most of whom won't stay more than a few months.
I keep remembering an interview in one of the trucking mags, where the president of Panther was bragging about his ability to pull 50 cargo vans to a shipper, on an hour's notice. In order to accomplish that (probably once in a lifetime deal) he needed to have 50 vans available, and that there were, says it all, for me.