If someone stops my movement, I am not good enough.
It depends on the context:
If we are doing kata both have to follow the choreography, both have a role to play, and uke stopping nage has no purpose except in extreme circumstances.
If we move away from the kata, and go into a more alive, spontaneous training, then yes. If your training partner is able to stop, evade or counter your technique that means you're not good enough.