This is a trap many companies frequently fall into. Without a Service Design or holistic CX approach, everyone has their own understanding of what
"good CX" is. The issue is, all of them may have been right in their own way, but none of them are aligned!

The larger a company is, the more danger there is of this happening - and the challenge becomes how to course correct as soon as possible.

There are many design frameworks (Double Diamond, Human Centred Design, Lean UX and more!). 

The best design approach and speed depends on the situation, but is always strongly aligned with business goals and timelines.