unless Mothers isn't as good as I thought it was.
Some of their stuff is very average, what particular product are you using.
If it's a liquid polish it's possibly full of fillers then a few blasts of water could be washing it away exposing the marks again.
Same goes for liquid waxes, they don't last.
A good wax has a high carnauba content and it's the carnauba that is the hard protective coating which also gives the product a longer life, a liquid will usually have a very low carnauba content and therefore not last.
Mothers like Meguiars have a business model which involves having you constantly purchasing their product, longevity isn't in their equation.
What they offer as a trade off to their short lifespan is easy use, easy on, easy off.
They sell a lot of product to mainstream car owners and they need to as they have enormous marketing and advertising budgets.
Mothers do make a very good metal polish which gives you a mirror finish on polished rims, I use it on a few of my cars and find if I need to do a repair with some wet and dry, it does as good a job at bring back the shine as anything else out there. I use it as a final finish.
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