For years and years, I've been surrounded by factoids about research into habit formation. Maintain an activity for 21 days, and then you'll feel compelled to keep it going! Make a plan for your activity, and then you'll stick with it! Visualize!

A lot of this kind of click-generating blog content takes a single paper and then dramatizes its findings. Bonus points for phrases like "researchers have discovered" and "scientifically proven."

Speaking from experience, motivation, judgment, and decision-making are easy fields to publish in. Experimental psychology labs have a relatively simple time getting and publishing results. Make a slight adjustment to an experimental protocol, recruit 30-60 psych undergraduates (many programs even make participation mandatory or offer extra credit for it), and voila, a paper.

As a result, many labs are publishing constantly just to survive. And very few experiments make a goal of following up with their participants weeks or months later. But that kind of stability is exactly what you want in your healthy habits!

Personally, I was surprised and disappointed to find that activities that had entered my routine had never actually become a habit. They were just a routine. When the routine changed, the "habit" disappeared. Before last year, my daily schedule included an hour at the gym after work. I maintained a consistent pattern for several years. After gyms closed, I just stopped going and didn't feel like anything was amiss.

Some time in the past year, I bought some simple home exercise equipment, such as a door-mounted pull-up bar and some adjustable barbells. I stuck to a consistent routine for two months. I have an entire notebook with pages filled with hashmarks in sets of five, counting sets of exercises. And then I also just stopped, for no apparent reason, and felt no urge to continue.