Dry irregular texture is appearing along the edges of a colour fill. What is the most likely cause?

Correct answer: Too little paint or moisture on the brush

The governing concept is brush loading and even paint flow. When the brush carries too little paint or moisture, it drags across the surface instead of releasing a continuous film, leaving dry, grainy or irregular marks, especially near edges. A balanced load, even moisture and controlled overlap normally improve smoothness, so options B, C and D describe helpful conditions rather than the likely cause.