How long do cutters typically last?

Just wondering if someone can share some insight in terms of how long cutters typically last. I imagine it depends on the materials that are being cut, but are there any general rules of thumb?

I’m noticing that .125" flat cutter is starting to leave wiggly strands of wood when I’m cutting hardwoods (maple and cherry.) I’m assuming this may be due to the fact that it’s getting dull?

Thanks

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