Giving up can be heavy, but sometimes it's necessary. I once had a personal website that I maintained for years, but ultimately had to abandon due to policy changes beyond my control. When I closed it down, I created a memorial page where thousands of users left messages, mostly expressing sadness, encouragement, and even offers to invest. I felt uplifted and apologetic. The experience showed me the meaning of perseverance.
On business in general? Never.
An idea or product? Depends. There is always another business opportunity so if something isn't working pretty quick, it might be worth it to switch. But there is no one-size-fits-all answer.
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