For me, the most important aspect of contributing on google map is to let people know before they have to visit or experience anything by their valuable time and money.
What I mean by letting them know is to honestly describe the situation, quality, quantity and everything else that is worth mentioning and maybe through a couple photos to make things more understandable; and when you did your part, it would be up to the people whether they wanted to travel a long distance to visit this place or they wanted to pay the hefty bill for a fancy dinner. In a perfect world when everyplace had enough rating and reviews, everyone will reach what they deserve, if they provide good services, treat people good and be fair they will receive many good reviews so they will have more and more people come to them and if not it would be the opposite; then it would be more like a “you reap what you sow” situation.
The most important thing is you have helped other people to save their time and money so they will make the best use out of it. Besides that, it’s fun to share your thoughts with other peoples, the business owners can benefit from the people opinions, and sometimes it’s just fun exploring the google map and checking other people reviews and see photos for your possible next plan.