Why do weed whackers/weed eaters often use plastic string and not metal wire?

Question

Why do weed whackers/weed eaters often use plastic string and not metal wire?

In: Other

Answer 1

As a quick aside, a lot of strimmers actually have changeable heads on them and you can swap out the plastic string head to one with a metal blade which is really good for more heavy duty stuff rather than grass.