Why would I need a better power supply if it's sped'd for 2A output and the mouse and keyboard was working working fine during boot?

I seemed to have solved this myself by simply going into "recovery" mode during boot and reinstalling the entire raspbian OS. Then, everything worked fine!

Just got my first raspberry pi 3 (or any raspberry pi for that matter) so please forgive me if I'm dumb. I did the initial setup using NOOBS lite (the full NOOBS download gave an error saying the compressed file was corrupt)... During the OS install, my mouse and keyboard both worked fine as I had t...