Design research is an essential part of design. Design cannot succeed without it.
The reason research is essential to design is that in any designed system, people are part of that system. If they participate, the system works. If they refuse, the system fails.
This participation is influenced and motivated by experiences. The right experience generates the right behaviors.
Research is how we stay in contact with these experiences.
It is how we ensure we are delivering the experiences that will influence and motivate the behaviors that will make our system flourish and deliver the desired results.