But you screwed up. Now what... Do you chose to say F*uck it and carry on screwing up more and more, or do you get on with trying to forgive yourself, correct our mistake and move on? There are many areas of people's lives (mine included) that I have seen the all or nothing mentality become more self sabotaging than the intial undesriable behaviour.
Diets, housework, homework, exercise, and even consuming intoxicants all tend to fall prey to this F*ck it mentality, where you chose to go on a downward spiral because you made one mistake.
Maybe you are 'on a diet' and you eat a bad meal, do you give yourself a free pass to gorge for the rest of the day on junk food so you can start again with a clean slate tomorrow, or at the start of next week "Because diets have to start on Mondays..." justifying carrying on doing the thing you know is not helping you get towards your goal.
Maybe you tell yourself at the start of the week you are going to cut down on how much weed you smoke, but by Wednesday you go out and buy a 20 bag and smoke every day until it's finished so you can quit without the temptation.
If you screw up, it is about how you deal with it afterwards is more important.
Day 10/365 days of personal development