Until a team has an account, a post and a scheduled post, the Social Media page starts with First steps: add the accounts you post to, write a post, and choose when it goes out. Each step is marked Done once the team has done it. Hide removes the steps for you in that team.
On a post in a team with no accounts, a team admin can select Add an account. The account is added to the team and switched on for that post, and the post opens again.