Brainstorming has been a very old & a successful method / path to solve any problem. It actually plays a vital role in derivation for reasoning to any problems. In simple terms, a manual guide to a problem.
Many follow & some disagree to this method. But after using the brainstorming method for a while long now, it has helped to solve problems at faster pace & with valid logic. Brainstorming is a great tool for focus group discussion where in some instances it lasted for days & in some just a day.In the process of brainstorming there are no ideas differentiated as good or bad, its a process where all ideas are considered & decided collectively.
This methodology holistically depends on how an individual or groups start inculcate in their respective fields.