Your GBP is what appears in Google Maps when someone searches for your trade. It shows your business name, reviews, phone number, and location. Google uses it to decide which 3 businesses to show in the local pack. If your profile isn't properly optimised, you're not in those top 3 spots.
Most tradesmen in Earl Shilton and Hinckley have a basic GBP with one category, no services listed, and a generic description. That's leaving money on the table. Google allows up to 10 categories and dozens of services - each one is a ranking opportunity.