Why Do We Half A** Stuff?

So before I get started I would just like to acknowledge how sore my body is!! Getting back into the normal routine of working out, after a two week break has been and adjustment. Always know it doesn't get easier, you just get better. I keep telling myself this as I try to lift my arms in pain lol. Anyways, I initially started todays blog talking about something along the lines of when things get hard push through blah blah blah. That last part is how I read it back to myself, and I had to delete and start over. I've been focusing on giving 120% to the things that I do, and finding myself having to redo some things because of rushing to "get it over with." This brought about a question to me: why do we half ass stuff?