erase history all is advised usually when sculpting and texturing your model(s). Certain cases like CPS ( connect poly Shape) depend on history and you shouldnt erase during this process.
History is most needed during animating and deforming. Animation is history dependant. In this stage Do Not delete your history.
Some functions like loft or bi-rail will leave your model attached to the surve used to generate them, use delete history to make them independant.
There are plenty of reasons to be aware of your history. Experament and you will see a number of reasons this is useful.
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And after calming me down with some orange slices and some fetal spooning,
E.T. revealed to me his singular purpose.
--TOOL, 10,000 Days---
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