In chapter 1 of The Power of Habit by Charles Duhigg, he introduces the the “Habit Loop” (Item 1).
This cycle is represented by 1) Cue, 2) Routine, 3) Reward… repeat. And, as Duhigg states on page-19, “Over time, this loop–cue, routing, reward; cue, routine, reward– becomes more and more automatic.”
The Cue, or trigger will tell your brain which pattern or habit should be used [ given a scenario ]. Next, a Routine is played out [ can be physical, mental or emotional ]. Finally the Reward; when the brain determines if this particular loop is worth remembering for future use.
Understanding this loop explains why our brain stops calculating, in relation tot he Habit Loop. In part because when a habit is formed, the brains will focus on other tasks.
Note, that…
• A habit can be replaced.
• A habit can be changed.
• A habit, can be ignored.
If you find yourself in a bad habit, then focus your attention to fight the habit that is no longer desirable, and replace it with a habit that you do want.
By ignoring the cues of a bad habit, and seeking new cues which will in turn create a new routine. And thus lead to a new reward.
Post Script
Author Mark Manson has a good article and podcast episode (3 Reasons Why You Make Terrible Decisions (And How To Stop)) on his web site that offers suggestions on how to make better decisions – thus improving your habits.