Rule of 3

I read a really interesting blog post here and it got me thinking..... 

I tried out the rule of 3

Day one, I got only 1 and 1/2 of the 3 done.

Day two I got 2 and 1/3 done and was happy with my progress....

Day 3 I got none done!!!!! and I realised things are not always as easy as they seem....

Then I did not know what to do whether to try and finish the 3 for the day before.....as I had done for days 1 and 2.....or to just set the 3 for day 3 as the 3 for day 4.....

I really hope I'm making sense....

HELP!!!! How does this work?