I know what you're thinking im about to bash obito cuz his replace "fake" world with "faker" world moon eye plan. But im not.
Is it Itachi for killing all of his clan and basically suiciding himself. No (I know im actually giving Itachi a break weird right?)
Tobirama and his Uchiha police..nope not even that.
Sasuke attacking all the kages..pretty dumb but he was high off of Sharingan boost so he gets a break.
No the worst plan a Naruto character had goes to Sakura. Lol. She actually believed she could kill Sasuke on her own, then Kakashi saves her and she just doesnt know how to stay out of trouble cuz she's at it again and is about to die so Naruto saves her this time. The people listed above I understand their reasoning and/or circumstances but Sakura how did you determine you could kill Sasuke especially after the 1st time you failed. Smh. If you agree good if you dont post who you think had the worst plan ever.