Fear of missing out
Fear of missing out (FOMO) some important technology in your career is a real feeling. Opportunities are always opening up, tantalizing you to follow them and ride the wave of the Next Big Thing, and you are missing out. Damn.
When do you have FOMO? It is when you are afraid that by not working on a specific technology, the “current” you is putting the “future” you to a significant disadvantage career-wise. It is when you worry that trying to land your next gig in your career won’t be easy because your skillset will be out of date.
I have learned to deal with FOMO. I have learned that missing out on something is not that big a deal. At some point or the other, I was awash with fear that at that very moment I was missing out by not being a guru on one or more of these - .NET, C#, Java, C++, every javascript framework, Ruby, Ruby on Rails, R, Matlab.
On the one hand, I have worked with people who develop years of expertise with a very specific technology or system and prefer to work only on that. On the other hand there are people who just care about building stuff with whatever is around that they can use. They are willing to put up with their lack of deep expertise in the tools that they use. The former miss out on everything outside of their expertise. The latter miss out on everything except what they have at hand for however long they have it.
Interestingly, both groups of people do great in their career because their work directly results in making things better for their team/customers/company. Your career is only as good as your ability to do that.
To rephrase - the more you work on making things better for the people involved (your team, customers, company), the more successful you are going to be in your career.
When someone hires you, it is because they feel pretty confident that you are going to make things better. Build your experience in doing that consistently, and your career will take care of itself. During the course of your career, a lot of things will change within and around your organization, and you cannot help but learn new things to keep at your goal of making things better. You can assess how well you are doing based on the amount of positive impact your work is having. Doing work that is impactful, like wrangling with terabytes of data and affecting the lives of millions of people even with a crummy tool, is still better for your career than doing something cutting edge with the new shiny thing that no one is using.
Learn whenever you can, whatever you can, no matter how irrelevant it might seem. Learn for the sake of learning, not for the sake of building a great career. If just doing your work teaches you things, then learn from it greedily. That is the kind of learning that sticks with you for a long time. Learn from your colleagues, learn from feedback. If you end up applying what you learned at your work, that is great. However, learning something and not using it at work will not affect your career. Doing work that does not make things better for others will.