[chipsanddip]

Hi, as Per that wrote this is a developer while I do the sales that come out of this, I'll answer this:

Mis-identifying a lead as a non-lead is potentially loosing out on a big deal that can make or break your company. You never know what email will lead to a quickly closed $30k ARR sale, which are golden for any SaaS startup.

The reverse has almost no consequences unless you're really going to town with the emailing and end up being flagged for spam. Usually people just ignore you (not so smart) or write back that it's not relevant.