There has to be a strong balance between back end knowledge and experience, and understanding how to navigate the more complex world of human interaction on the front end.
It’s a bit like riding a bike. If you only have the front end – customer service skills – you’re driving a unicycle. At best it’s entertaining.
If you only have the back end – technical skills – you may be getting a workout but you’re not covering any ground. It’s spin class.
Welding the two together in an inseparable bond is the key to success. You can ride this metaphor down the road as far as you like.