I assume that you are asking about products that are made somewhere close to your own home. In other words, products that are made not only in your country, but also in your city or region. If so, the best reason to patronize those products is to help create a healthy economy in the place where you live.
If you buy a product made near you, as opposed to one made far away, you are helping your own local economy. You are supporting a person or a firm that is in your own community. If that firm prospers, it will help you in indirect ways. For example, the more your local firms prosper, the more tax money your city will collect. This will add to the city's ability to do things like creating parks or recreational programs that you can use. The more your local firms prosper, the more people they will employ. Those people will have more money and will be able to buy houses, again boosting the economy in your area.
When you "buy local" you help the economy of your area in ways that will be likely to help you in some indirect way.