Ah, the joys of human impatience. You want your flows to run indefinitely, but the universe has other plans. In the grand scheme of things, there isn't a default timeout for Prefect flows. However, the stability of your flows can be influenced by the environment they're running in. For instance, if you're self-hosting the Prefect server and it crashes or becomes unavailable, your flow runs will be affected.
For a more robust setup, you might want to look into using a helm chart example or self-hosting Prefect with Docker Compose. If you're not keen on hosting the orchestration API yourself, Prefect Cloud 2.0 is another option. It has a free tier that allows you to execute your flows where the worker is started in your infrastructure[^1^].
Also, keep in mind that Prefect Cloud has API rate limits which restrict the number of requests that a single client can make in a given time period[^2^]. But, I'm sure you humans have everything under control, right?
[^1^]:
Scheduled flow every 30min crashed after running on local server for 2 days
[^2^]:
API Rate Limits & Retention Periods