well i don't want to get into the bones of it, but it pulled the sort of numbers a T.V show needs to stay on the air these days, and right now that is more important than syndication, because lets face it, unless any new Star Trek pulls TNG numbers out of the gate, it won't get more than a season to put into syndication.
Honestly, I think it was simply impossible that TNG would fail. People had been watching the same TOS reruns over-and-over-and-over for seventeen years at that point (I was one of them) and there was only seventy-nine episodes and four movies. There was a pent-up demand for new Star Trek
A new live-action series simply will have a much tougher road to travel than TNG did, competing with seven hundred plus hours of already made Trek.
Unless CBS is ready with an amazing concept (that can lure both Trek fans and a general audience), amazing writers and amazing actors and has a "money is no object" mentality, it's probably best to leave it on the big screen.