The three things that decide local rankings
Google's local algorithm rests on three pillars: Relevance, Distance, and Prominence. You can't change distance — Google knows where the searcher is. But you control the other two.
Relevance is how well your profile and site match what's being searched. A plumber listed only as "Acme Services LLC" with no category will lose to a competitor listed as "Acme Plumbing — Emergency Plumber" with the right service categories ticked.
Prominence is Google's measure of how well-known your business is in the real world. It's driven by review volume and rating, citations (mentions of your NAP across the web), inbound links to your site, and how often people search for your business by name. This is the slow-build half of local SEO — and the half competitors can't shortcut.