Gmail never delete mail !

This is no news that Google will keep your mail even you deleted them, normally if you clean the trash you will not see those deleted mail again, as least for what we can see. But I found that those deleted mail ended up in other sorted folder, namely 'updates' and 'promotions', but there is nothing on the trash and I did not move them, this is extremely annoying and confusing, if not I am using Android I will not use Gmail at all !