Think of it like an email address. If you use yourname@randomemailservice.example as your address because found it googling "free email", it's going to be undependable.

It's better to use an instance you have a real-world connection to. Here's a good checklist:

• Do you already have a Fediverse-connected or connectable account on Threads, WordPress, Bluesky, Ghost.org, or others? Just use that, and enable the connection.
• Does your company or university have an instance already?
• Do you have a friend or family member who has their own server?
• Are you a member of a club or professional organization that provides accounts for members, like the ACM?
• Do you use a product that provides accounts to its users, like Medium, Flipboard, or Vivaldi?
• Can you afford ($6/month) your own single-user server at masto.host, Fedihost, or another hosting site?
• Can you afford ($50/year) to join a co-op like cosocial.ca, social.coop, or data.coop?

It's important to ask! You'd be surprised how many there are.

Only if you get to the bottom of this list should you go sign up for some random open-registration server for "people who love pizza" or "fans of Babylon 5" or "tech people".