Actually, although their time is very limited, there really isn't much excuse for slacking off on details like Bruton described. Take an anime like Bleach for example. They push full-length, 23 minute episodes out once a week, and the artwork and attention to detail in the characters and the environments continues to amaze me. And that's not even counting the ridiculous special effects in some episodes. The Land Before Time tv series is probably just on a much lower budget, hence less people to work on it, because if they really wanted to and had the money, they could easily make the episodes of movie quality.