We are doing-thinking beings. Our minds and bodies are made to create and through creation we learn and grow.
There is an inseparable link between the physical act of performing an action and our human intellect.
We don't learn by simply being told about something, it is why we have forgotten so much we have been taught in school - we learn through engagement, and engagement means action and creation.
By creating we build experience and by making that creation a conscious process, by targeting the practice, by having intention, we grow leaps and bounds...
Too little thought and too much action leads us to hit ceilings in our skill and wasted effort. We don't target the weaknesses - we repeat the same process expecting different results, it feels like beating a piece of dead meat...
Too little action and too much thought leads to tricking ourselves into thinking we have made meaningful progress without actually doing so. We intellectualize, overthink and rationalize inaction, chalking it up as preparation or inadequacy.
There must be action and then thought about the action to make effective progress.
They are two sides of the same coin.