What are the drawbacks to remove background by hand?

Removing background by hand means manual cutting and trimming pictures step by step. It has many obvious downsides. It is easy to leave jagged edges, miss tiny details and cause uneven cropping effect. Manual operation cannot handle complex scenes like hair, thin lines and fuzzy outlines well. Compared with manual work, AutoAGC is much better. It uses smart AI to finish matting automatically, edges are smooth and natural, no flaws left, and totally avoids all defects brought by manual background removal.