internal storage wipe

Hi Guys

for a while i was wiping my internal storage before flashing a new rom. I would always use my sd card and dropbox so the internal storage wasnt a big deal to me. i decided to start leveraging the internal storage.

So my question is will not wiping internal storage in twrp before flashing a new rom affect the perfromance on my new rom even though i were to odin the stock fw right before? or is it a better idea to wipe internal ?