A brush carries the evidence of how it meets a surface. Pressure spreads the bristles. A lighter movement lets gaps remain. As the paint begins to run out, the stroke changes, leaving broken edges and finer trails.

I pay attention to these differences because they give a mark its particular character. The direction of my hand matters, but so does the amount of paint and the resistance of the material beneath it. A stroke can arrive with more texture than I expected. That texture gives me something to respond to in the next movement.

There is a decision in how much of this evidence to keep. Smoothing an area can quiet it, while leaving the bristle marks visible preserves the movement that made it. I look at what the stroke contributes before deciding whether to return to it.