Daniel Pink explains the fresh start effect: temporal landmarks like Mondays or birthdays act as mental reset buttons that make people more likely to start and stick with new goals. Scheduling goal-related actions on these dates, rather than random ones, significantly increases success rates.
It's called the fresh start effect. And a way to understand the fresh start effect is like this, that certain dates, certain days, certain dates are what social psychologists call temporal landmarks. What they do is essentially they operate as kind of a restart. What they say is that on certain days that are fresh start days, you essentially relegate your previous bad self to the past and open up a fresh ledger on your new self. You're more likely to start something and you're more likely to succeed while starting it. So what does this mean? You want to start something, you're probably better off doing it on a Monday rather than on a Thursday. You're probably better doing it on the day after your birthday rather than 3 days before your birthday.
