Interesting question and one that I'm pondering a lot at the moment.
Having taken early retirement 9 years ago with a decent pension from a pretty stressful management job I took on a part-time admin/ICT job to keep me from stagnating and bring in a bit of cash. That job is now a comfortable flexible 20 hours a week and reasonably interesting so I'm not desperate to give it up.
Also started my own consultancy business a few years ago as a small sideline, but it's grown and is very successful, but time-consuming.
So on the one hand, I'm happy where I am, but on the other I want fairly soon to be able to just take off for a few months at a time and travel the world. This will happen at some point, but not sure when. Don't want to leave it too late.