I find it hard to keep going with some things. I don't go to the gym. I can't be bothered writing three drafts of a blog post. I don't really want to fill the holes in my wall from where my plasma TV bracket used to be.
If I have to do something I don't want to do, it has to be really easy to start and really easy to stop. That's why I play squash instead of going swimming. With squash, I drive down to the squash court 2 minutes away, smash the fuck out of a squash ball for 45 minutes and go home. Done. If I felt like playing squash right now, I could be there in 5 minutes, playing. Swimming, on the other hand, takes forever. You have to find your trunks, drive down, get a locker, get changed, jump in and swim at a pace slower than I can walk, get out, have a shower, find your locker, get changed, drive home. And I'll have red eyes from the chlorine. It takes too long.
On the flip side, if I want to stop something, I have to make it as tedious as possible to start and stop. When I was at college I decided I drank too much at home. I had a fridge in my room for beer, so beer was always available. When I bought beer I'd always buy a bulk pack (for cost more than anything). So there was always lots of beer available. In order to stop, I took my fridge and gave it to my parents for their holiday home in Montenegro. Then I took the bulk packs of beer and put them in the garage. Finally I put a pack of Pepsi in my bedroom. Going to get a beer from the garage at 10pm is less appealing to me than drinking a Pepsi that's within an arms reach.
When you want to get something done, its easier to move around problems rather than try to overcome them. Yes its cheating, but you'll get the job done. Or as an ancient Daoist text says-
"In all the world, nothing is more supple or weak than water; Yet nothing can surpass it for attacking what is stiff and strong."