I always thought of the 'different result' as meaning improvement, and the action in repetition as being suboptimal. Thereby no matter how much you practice you

I always thought of the 'different result' as meaning improvement, and the action in repetition as being suboptimal. Thereby no matter how much you practice you will be at best improving sub-optimally. This makes particular sense when you're practicing a musical instrument, bad habits will be more and more engraved as you repeat more. The best instrument players are those who have been taught or self-discovered good ways to improve, and put in the hard practice/repetition.