Pinking the raw edges of yardage before washing helps with the raveling problem.
Pinking the edges of applique pieces reduces the need for clipping curved edges.
Sometimes I will pink applique pieces and then not turn the edges under, that makes an interesting edge
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When I am crafting with felt, I will often pink the felt edges for the decorative edge as well.
In dressmaking, I will pink most of the seam allowances, controls fraying and makes a more finished looking seam. The "valley", not the peak usually needs to run along the cutting line.
BUT, NEVER use the pinking shears with loosely woven fabrics, each cut thread really unravels quickly.