[monroewalker]

Apologies if this is already covered by other responses, but one thing to consider is the incredible pace of change in the software industry. In a matter of years, new technology can go from being unheard of to being an industry standard. New languages come along and supplant older ones, new services and tooling are created which become the de facto means of building certain types of software.

There are lots of jobs in the industry, especially at larger and older companies, which will just involve working on systems with a mostly static set of technologies being used, but it's worth considering the effort it takes to stay modern with your skills and experience if you're not just trying to stick it out with one company