There's that thing that happens where you get to work and a half hour later someone who happened to be outside comes in and tells you that your tire is flat. Damn it! You think to yourself. So you do two things. Firstly you go out and check the bike. Sure enough the tire is completely flat, and after inspection you find a small sharp rock (shale?) in the tire. Seriously? So on your lunch hour you walk a half mile then take the train a mile or so then walk another half mile to get home, wherein you hop on your old workhorse of a cargo bike--which you haven't ridden in a while--and ride it back to work so you can tow the other bike home after the workday is done.