The best day of learning a hard skill is the day it gets boring. Boring means your hands know it now.

Boring is the finish line, not the warning sign. While something is still thrilling, your attention is being spent on the difficulty itself, which means your hands have not taken it over yet. The day the chord change feels dull is the day it has moved somewhere below conscious effort, and that is exactly what you were practising for.

When boredom arrives, treat it as a promotion rather than as a reason to stop. Add difficulty: faster, longer, in a harder key, in front of somebody. Then wait for the new thing to get boring too.