When do you decide to move ahead from your product?

I have made two different products (none worked). When starting with the first product, I thought of marketing it through social media and paid ads. But, a few weeks later, I came to realize that the market I am trying to make my customers are not really a good fit for the product and that the market is not having this problem yet. So, I moved from it after a few weeks.

Then, with the second product, it was a completely opposite situation. I created a product which had extremely competitive market and several other devs had created the same product as mine or even better once (regading automation). A few weeks later I moved on from that.

One lesson learned, always do market and competition research. When do you decide to leave the product and conclude it is not worth it now?