Design Process Summary
Any 'step-by-step' process, with recommended UX tools and procedures, can fit perfectly when the variables are ideal. And, in many cases, they are not, such as the abovementioned tight deadlines, no resources for research, and other issues. On top of that, any problem a designer needs to solve comes with market volatility.
So, more important than any design process rules carved in stone is the ability to be flexible and agile. A good design process is also the ability to understand how to fit scenarios like adjusting to a developer's skillset, compromising a sudden shorter timeline, or accommodating the goals of another team.