We tend to gravitate towards the activities that excite us, and during our excitement it's hard to step away and do something else. This is especially the case with workaholics who enjoy their work and can't seem to call it a day.
I've found that it's important to maintain boundaries so I can create pockets of time and attention for other areas of my life beyond work. I used to spend every waking moment either working or thinking about work.
It's not that work is the only thing I enjoy, and it wasn't always excitement. In fact, my obsession with work was fueled by stress: financial stress, social stress (not wanting to disappoint others), and psychological stress (worrying about personal failures and what those mean about my own abilities).
Boundaries can be set based on time (not doing work in the morning, or working on a side project in the morning, or reserving time for meditation or exercise), based on location (not working at home or not using digital devices in the bedroom), and based on people (I won't use my phone when around loved ones).
Keeping boundaries ensures you don't allow activities to take over your life and distract you from a more holistic definition of success, where success isn't defined by only one aspect of life.
What boundaries do you feel you need to maintain to live the life you want?