@sarah.lauden 

It depends what is your purpose with the subscribers..

If you want each separate form subscribers to go in different flow its easier to set up if you add it to different lists.

But also for example if you want all your new subscribers to go through pre-purchase flow than its easier to subscribe them to 1 list.

What we usually do is we use 2 different forms and 2 different lists. 

1 is newsletter list with pop up showing on homepage, and this subscribers we count as general where we put them through all general flows.

2 is exit intent list and this subscribers we have special exit intent flow for providing them with the exit intent discount. This subscribers we don’t send pre-purchase emails to.

And yes however you do it same list than different segments, or different lists from the start it doesn’t make much difference since both are easy to create, it only depends what are you using most often. If you create different lists how often would you use them as separate lists? Our answer is not that much so we don’t do it that way.