I went into the kitchen to throw away a tissue. I noticed the trash was full. I thought: "Oh, I'll just take out the garbage." However, I then noticed that the top of the trash can was rather dirty, so I went to get a wet paper towel to clean it off. I turned to find that the paper towels were out.
So then I went downstairs to get some more paper towels. I remembered that we had laundry to put away, and that later today, when we usually do laundry, we would be out to the hospital for a tour. We had to do laundry earlier, likely about right now.
I got the paper towels, came back upstairs, cleaned the trash can, and while I was taking out the trash, noticed the recycling bin was also full. So that had to be taken out, too.
This situation, along with many others (e.g., fixing anything in the house; replacing a light switch ended up taking half-a freakin' day), resulted in a conclusion: There is never only One Thing to Do. There are always Many Things to Do. To think otherwise is to commit a fallacy.
In other words: One task is Many.
"I'll just do this One Thing." Yeah, right!