I frequently have arguments with people about wasting time “re-doing” things they spent time on already. They’ll say things like, “I know this isn’t the best solution, but if we change it now, we will have wasted the time we spent making it.”
Here’s the thing. You’ve only wasted that time if you never learn from it and fix it.
If you spent your time making something that isn’t very good, and has little or no value, then you have wasted it. If, however, you spend some more time making a better, high-value, thing, based on what you learned, then it was only a small investment in the resulting high-value product.