Am i useless??? OF COURSE not Not Not !!!

Today working keep doing something wrong...when i stapled the book, i use the wrong size of "bullets"...after finish removing the paint on the book cover, i forget to throw away the cotton stick ( actually i dunno that i need to throw them away because i didn't see anyone throwing)...while taping the book, i use the wrong technique and that's why i only can tap one book while other already tapped three books....doing so many things wrongly, feel like i'm so useless...feel like i'm loser...i'm sad but that feeling only lasts for a few minutes...after that, i told myself i must change...i will become a better person...if wrong for this time, next time don't do it anymore...take it as a lesson...everyone will do mistake...in addition, IF WE NEVER DO WRONG, WE WILL NEVER BE BETTER...when we see out mistake then only we can change to become a better person....