Abrasive flap wheels, with coated abrasive rectangular strips attached radially to a hub like fan blades, are widely used in several industries as a surface finishing tool. The compliance of the flap wheel is a key reason for its wide use as it conforms to the work surface and polishes large flat and curved, convex and concave, surfaces. While polishing the flaps get worn out and get consumed as they become shorter in length, and this changes their compliance behavior. The radial change in length also alters the gap between flaps and hence flap-to-flap interactions. We study using high speed camera imaging both the compliance behavior of the flaps and how the flaps interact with each other. The images are used to determine quantifiable parameters related to compliance and flap interactions such as contact length and its location, flap contact count, flap bending angle, curvature, and tip speed. These quantified parameters are then correlated with polishing performance signatures, such as contact area, forces and material removal rate. As the flaps wear out, significant changes in polishing signatures are observed and these changes can be explained using the compliance behavioral changes in the flap. This study helps in a systematic way to design and use abrasive flap wheels.