I may have to disagree with this sentiment. I think a bad shot is subjective depending upon one's definition and the player being discussed.
I think it's a sliding scale. As in, the most ideal shot for, say, David Robinson, is a dunk. For Stephen Curry, it's a wide open layup. From there, one works their way out to less and less reliable forms of scoring until that line between "less efficient" and "bad" is crossed. A David Robinson mid-range jumper is less efficient and accurate than his layups, dunks, and jump hooks, but it was still a worthy and dangerous weapon. Would Robinson's field goal percentage dip if all he took were mid-range jumpers? Absolutely. But that doesn't mean it was a bad shot for him. Robinson wouldn't likely hit "bad shot selection" territory until he backed up around 21 feet.
Similarly, Curry's penchant for taking and making seemingly difficult shots at odd times and from weird angles is unlike any shooter I've ever seen in my life. Obviously, if Robinson attempted
any of the shots Curry did of that nature, they'd be awful, awful shots, because the chances of hitting would be so low. However, Curry's ability to succeed in that realm is akin to Robinson's mid-range game in that those shots may go in at a lower rate than open J's, but the rate at which he
does hit them (more accurately than anyone I've ever seen) is a
huge part of what makes him so dangerous.
My wording feels poor but basically, what may be declared a bad shot for one player is not necessarily so for another.