Forever is the default, not the answer
Almost every tool keeps recordings until you delete them, and almost nobody deletes anything. Two years in, that is a searchable archive of every conversation you have had — which is genuinely valuable, and also a thing that exists.
The question worth asking is not whether the archive is useful. It is whether you would be comfortable with it existing in a situation you have not yet imagined.
The three categories
Recordings whose value is the summary. Most meetings. Once the digest is written and the follow-ups are extracted, the audio has done its job. These can go in weeks.
Recordings whose value is the exact wording. Negotiations, client instructions, anything that could later be disputed. These are worth keeping as long as the matter is live, and often longer.
Recordings that should not have been made. A conversation that turned personal, something recorded by accident. Delete these when you notice, not at a review later.
Set a rule, not an intention
“I will clear these out periodically” never happens. A rule does: keep everything for ninety days, keep flagged items indefinitely, delete the rest.
The specific period matters less than the fact that there is one and that it runs without you.
What deleting should actually mean
Ask your tool directly: does deleting remove the audio file, or the row in a list? These are very different, and a surprising number of products do the second.
Ours removes the stored audio, and closing an account erases everything we hold. We say this on our security page because it is the kind of claim a company should be willing to write down.
If other people are in the recording
They are, always. Retention is not purely your decision when the archive contains other people's words, and a request to delete something is worth honouring even when nothing obliges you to.
Regulated sectors have their own retention rules, which may require keeping things longer than you would choose. Check what applies to you rather than assuming.