Mostly because at the time of choosing a private repository hosting service, GitHub didn't offer free private repos. I used to host all my private projects with Bitbucket, but I like the GitLab interface.
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Why aren't you using github also for private projects?
Mostly because at the time of choosing a private repository hosting service, GitHub didn't offer free private repos. I used to host all my private projects with Bitbucket, but I like the GitLab interface.