That is an interesting question. In my own career I've changed jobs several times, also at the same company (at Dell for +10 yrs now). Change is great and if you can, you should embrace it. Very often change takes you out of your comfort zone, and that's when you start to learn and develop.
So far - what I've always done is to change 1 aspect (out of comfort zone) and keep another aspect as is (inside comfort zone). Let me give you an example.
As a product manager I'm responsible for a specific product in my region (in my case, Europe, Middle East and Africa). If you look at it - you'll see that there are 2 main aspects; 1. the product that you work on, 2. the region that you work in. If I were to make a change in my career, I would in this case either look at working on a different product - but staying in this region, or work on the same product but in a different region. You get my point? That way you'll be comfortable enough to be able to cope with the change outside of your comfort zone.
This has worked very well for me and has really kept my career fun and interesting.
Hope that helps a bit!
All the best!
What an interesting question! Really made me have to stop and think.
I was a career law enforcement officer. While many officers use their commissions to work side jobs, what I did differently came after I retired. I brought a lawsuit against my department (long story, not relevant to the question. . . ) In working side by side with my attorney on my case and a companion case, I was able to showcase my abilities. After the case settled, he hired me on a freelance basis. From there, I was able to also secure work for other attorneys. The cases were often complex, and interesting, including several custodial death cases - people who died while in police custody. This allowed me to dabble in law to a degree sufficient to satisfy my urge to do so, without having to go to law school.
I ultimately ended up in a very technical career that requires special skills. I would have completed my college degree work earlier in my life. I did not get my Bachelor's degree until i was 35 and then my Masters degree at 38. I did manage to be successful in my career without degrees, but there were opportunities for me to move faster if I had gone to college and really learned my career.