doesn't cut the mustard

1. Is unable to work or operate in a satisfactory manner. I need a new worker from the temp agency—the one you sent over keeps mixing up orders and just doesn't cut the mustard. This toaster doesn't cut the mustard anymore. No matter what setting you choose, your toast comes out charred! Based on his consistently low sales numbers, I think it's time to let Bill go. He just doesn't cut the mustard.

2. Is not at an acceptable level or of an acceptable standard. I know you highly recommended this guy, but he doesn't cut the mustard. He just can't keep up when things get busy. I have to warn you, Jenkins, your last few reports didn't quite cut the mustard. You're going to need to improve if you want to keep your job here. If you've pulled a muscle two games into the season, your pregame preparation clearly doesn't cut the mustard!

not cut the mustard

To not be at a satisfactory or requisite level; to not successfully complete or accomplish a desired or expected result. The underdog gave a brilliant performance in the ring, but he just could not cut the mustard against the returning champion. I have to warn you, Jenkins, your last few reports haven't quite cut the mustard. You're going to need to improve if you want to keep your job here.