Online Poker Tournament Rankings

Ok this is my first post on here so bare with me if its abit rubbish. Ok so since the start of October i decided to really go for being a major player in the big mtt's on FTP, and have gone pretty deep in alot of tourneys recently having polished off my early game which i feel is pretty sound now. How ever im increasingly frustrated with my late stage game as i keep missing final tables, the last few i can remember 10th, 11th and last night 12th. Is there something im doing wrong or is it just