Doug is a firm believer in reciprocity (said with the same tone as Big Daddy says "mendacity!" in Cat on a Hot Tin Roof). Reciprocity, karma, what comes around goes around, etc. . .
Anyway, when I worked at the law firm, we had to keep track of our hours so that our clients would be billed for the time spent on their cases. This was very difficult for me because of the many times I would interrupt work on one matter to answer the phone, answer email, talk to someone, work on another matter or look up something. I would forget to write down one of the starting or ending times and then have a hard time piecing together my day. Then, when I worked for the company, there was no billing (pshew!). Now, however, my contract says I must bill for my time every two weeks.