Let's get straight to it then!
1. Telling myself things I know aren't true / Deciding to not do things I know I will do / Being foolish when I know I shouldn't have to. I am totally using this as a song idea for my next Coursera songwriting assignment! If it can rhyme, why not make it a song that's sublime? :D
2. Starting to read a book by dividing number of all the pages by the number of days I want to finish it in and then not following through with the plan. I'll go to bed at 11 pm thinking I have my quota of 56 pages to read for the day and somehow doze off on the 8th page only to find myself awake again, online on my phone or on one of those unending YouTube sprees that end only when your eyeballs start to feel like they've got paper cuts and despite you, you're off to sleep.
3. You know when you have a little product left in your bathroom in that bottle, shampoo, shower gel, oil, whatever, on a Saturday and you decide you'll finish it on Sunday so you can start the new bottle on a Monday, (how ideal and perfect), but then on Sunday you realise you underestimated how much was left and are forced to be wasteful just so you can fulfill that stupid OCD of starting the new one on a Monday. I always think "why did I think I would need this much shampoo? Maybe I should shower again later today just so I don't over shampoo now, but then wouldn't that be over shampooing anyway, do I want to shampoo twice in one go or twice in the day?" It's a problem. FWP, but still!
4. Every single time I have ever baked something on my own, I decide to not follow the recipe, make my own changes (which at the time seem sensible), put everything in the mixing bowl in one shot instead of doing the dry ones first and then adding the wet ones gradually like it's supposed to be done. And then because of how much I hate being wasteful, tell myself and everyone they're well done and force myself to eat 3 disgustingly salty muffins. (Can you believe I didn't put sugar in a peanut butter banana and chocolate muffin recipe?)
5. Being impulsive. I really don't have a ready example, but 9 times out of 10 when I've acted on impulse I end up being annoyed that I didn't think things through or even so much as imagine the consequences lol.