The phrase "accidental byproduct" means something that was not intended or planned, but happened as a result of another action or process. Full definition
And the Anthropocene is strewn with many more accidental byproducts of human ambition and ingenuity, as we've changed the chemistry of the global ocean and atmosphere. (corporateknights.com)
I believe that any affinity we find in ourselves for love, goodness, beauty and truth aren't an accidental byproduct of an undirected evolutionary process but signs within us of the image of the God that Bart no longer believes in. (premierchristianity.com)
The disgusting taste of a rotten apple, in their view, was more likely an accidental byproduct of its breakdown by microbes. (sciencemag.org)