Why change?

I have already asked a question about migrating an Oracle database to Caché, and I was promptly answered. Now, I have one more question, however it is more conceptual. In general, any tool defends its benefits, and looking at Caché's, among many, there is a lot of talk about speed. The question is, if I already have a database, and at the moment, its performance is not a problem, I would like to know what else could influence the change of this database? Remembering that it is functional and without any apparent problem.