1. a tendency to do nothing or to remain unchanged
2. a property of matter by which it continues in its existing state of rest or uniform motion in a straight line unless that state is changed by an external force.
Inertia governs most of our life. It's a pretty accurate predictor of our short term future. Wondering what you will be doing 15 minutes from now? Likely the same thing that you are doing this very moment.
Staying in inertia is the path of least resistance. It's much easier to have Netflix auto-play the next episode and keep watching than to switch off the TV. It's also much easier to continue with the same habits you've had for 15 years, whether they serve your goals or not.
And sometimes, inertia is a good thing. When you write on 200WAD, you get a little streak going, and you just have to continue on this path. Keep doing what you're already doing.
But often, inertia means following routines mindlessly, without recognizing if this makes you happy, adds any meaning to your life, or brings you closer to your goals. Those are the patterns we should break.
How? This takes a lot of practice. Try to be mindful of every moment.