Essentially. Generally, one of the most important factors of an anime production is the planning. So that has a lot to do with it.
Some shows, original projects mainly, are usually created and in planning for years before the anime starts. Dennou Coil was of course in planning for YEARS. Gurren Lagann was in planning for a few years too, same with E7. Bones' upcoming show Bounen no Xamdou has been in planning since 2006. Etc.
If a show has a rushed production schedule from the start, it will have a huge effect on the quality of the overall production. For example I seriously doubt that "generic dumbfuck harem animu" is in planning for very long before production starts since a lot of those kinds of shows are greenlit due to current trends and whatever.