Cybersecurity: Read Team vs. Blue Team

Should a company investing in building an offensive security "Red Team" so they can skillfully discover vulnerabilities in their systems, or a "Blue Team" so they can skillfully react and even prevent those vulnerabilities?

From https://securitytrails.com/blog/cybersecurity-red-blue-team :

There is no “red team is better than blue,” no benefit to picking sides or investing in only one. The important thing is remembering that the goal of both sides is to prevent cyber crimes.

One idea born out of trying to reconcile red and blue teams is the creation of purple teams. Purple teaming is a concept that does not truly describe the existence of a brand new team, it’s rather a combination of both the red team and blue team. It engages both teams to work together.