[ken]

I don't think there's any one single blocker that's keeping me on GitHub. It's just a bunch of little annoyances with GitLab that add up to make it not worth it -- either UI quirks, or ways in which third-party tools integrate just a little more easily with GitHub.

Yes, GitHub absolutely has a bunch of annoyances, too. (I listed a bunch of them here on HN in response to a question by Nat, just the other day!) If everyone were using GitLab first, we'd probably find excuses to put off switching to GitHub, too.

To attract users, you've got to have a pull. If that's "open source", then it needs to be a way in which the closed-source nature of GitHub is hurting my daily workflow. If it's "user interface", you need to be such an improvement over GitHub that it's worth the cost of switching. If it's "cost", that's tough because GitHub dropped prices and is now $0 for many users, and you probably don't want to get in a price war with Microsoft (see: Netscape).

It doesn't have to be the same pull for every customer, but every customer needs at least one.

"We're just as good as that big popular project" isn't a pull. I've seen hundreds of projects try that, and it never works.

[Rapzid]

This sums up my attitude towards it. Opportunity costs factor into switching cost; am I getting enough ROI for the switching costs vs something else I could be working on?