Does all anime have a Complete collection after they have all came out?

Answer 1

No. If it isn't popular enough, it will not come out with a complete collection. However, this usually only occurs if the thinpack (single dvd releases) get canceled as well. This was the case that happened with Cardcaptors (ie Card Captor Sakura). Although, there usually is a release that will come out with just subtitles (no english dubs or extra features)- if Japan actually releases the complete collection.