10 = for me no film has achieved this. (if you check IMDB for an example top 100 list notice none get an actual 10/10)
9 = All time classics legendary films e.g. Bladerunner, Empire Strikes Back, Raiders etc would get in here. (just)
8 = Great films just short of legendary (quite a wide remit as most of films i really like and class as excellent would fall between 8 - 9) e.g. Interstellar, Cloud Atlas, Brazil, Matrix Trilogy, Inception, 12 monkeys etc)
7/10 = decent enough to very good e.g. John Wick, Captain America Civil War, + loads more
if it gets between 6 - 7 then for me it was worth watching and entertaining a bit but i will probably forget it ie its a bit meh. So a film for me has to maintain a 6 minimum throughout otherwise i'll switch it off (and wikipedia the ending if i need to). But has there ever been a film where the first half has been complete crud 3 out of 10 and the 2nd half has been utterly magnificent at least 8 or 9 ?
Why force yourself to watch complete garbage?