When do you keep renewing a quiet domain?

Some domains sit for years with no offers, no project, and almost no traffic. Still, they get renewed for another year.

For SEO or flipping, what makes a domain worth keeping?

Clean history, niche potential, backlinks, future project value, or just waiting for the right buyer?

If you don't plan on using the domain, no point in retaining it, unless it is highly brandable, single word domain and you're sure you'll get an offer some time in the future.

I once sat on a domain, paying renewal fee for 11 years, didn't get any offer, even when I tried to actively sell it. Was a highly brandable domain name in travel niche.

For me, it feels like a mix of well kept history, good quality backlinks, topic relevance, and future upside. If a domain has a solid backlink profile or actually matches the project I want to build later then sure, it is worth renewing. Otherwise, I usually let it expire instead of paying renewal fees year after year, because it just isnt sensible.

If a particular domain has a good reputation and valuable backlinks as well as a purpose, then I will retain the domain; otherwise, keeping any random domains without a brand or niche value just loses money