Most people make small progressions even after they've plateaud. We pick up a little move or a new insight now and then. It's better than being a stopped clock that's only right twice a day, but we can do so much more.
One reason we don't - IMO, YMMV etc.: It can mean losing your bearings big time. Owning up to a LOT of wasted time. Saying to ourselves, "I have to do what I haven't been doing!" When we stop resting on our accomplishments, we can start to believe they are disappointments.
That's not the way to change. What we have are skill needs. They are a chance, and a desire, to build actively on what we already have. Think of it as new growth. Keeping the old oak green and broadening its shade.