There is a huge burnout rate in truck driving. These places such as J. B. Hunt, Schneider's, etc., wouldn't constantly advertise for and recruit drivers if there weren't such a colossal turnover. You need to ask why.
Those of us with long memories remember a nasty truckers' strike in the early 1980s that led to violence and gunplay against strikebreakers and "scabs". In the wake of that, the US government released a report—mentioned in Car and Driver—that essentially said there were too many trucks on US roads anyway and in particular too many independent truckers and marginal trucking firms. All these years later, the number of trucks on US roads has exploded, even though many companies that had been major players in the field, such as Hall's, are long gone.
When I drive on Interstate 81 in Virginia's mountains, it is wall-to-wall big rigs most of the time. The problem with too many trucks has intensified since that report, and there are too many drivers chasing the available loads. That obviously isn't good for pay and working conditions, and it can't continue. More and more intelligent people are asking why so many trucks are driving long distances when trains would be more suitable for lengthy runs with most cargo. The Richmond Times-Dispatch noted that roughly 60% of trucks on the 324 miles of I-81 in Virginia simply pass through without stopping—not beginning or ending their runs nor stopping in Virginia. A more rational transportation policy would ask why much of this cargo can't be diverted to the Norfolk Southern train tracks that roughly parallel I-81 from Knoxville, Tennessee, to Harrisburg, Pennsylvania.
One colleague left work to drive trucks but came back after a year and a half when the small firm he drove for folded. He told me that he had driven to California and back hauling loads. This also raises the question why trains can't be used for such runs. Change of some sort sems inevitable, and it can't be good for drivers.
To sum up, I say don't do it. I hadn't heard about the problems that Chris142 describes with drivers having to foot the bills for problems, but with the way companies run things today, I can't say I'm surprised. I wouldn't enter the field.