They'll no doubt be possible several factors to consider
A Possible general trend to falling audiance numbers
Audiances wanting shows to hit the ground running
When TNG came out, it had virtually no competition in the genre, from the early 90's more and more Sci-Fi was being produced.
Decreasing Ad revenue
Not taking risks and playing it overly safe.
Increase use of time delayed viewing, so those not counting into the final rating.