Puzzled

Puzzled
I was on mc yesterday and asked my colleague (call her A) to help me run my daily job but she replied asking if colleague B will be in. Colleague B was supposed to be my backup but he always comes in office quite late so thought since colleague A is in everyday from 7.45am, its more convenient so that data updates will not be late. So anyway, after I replied again saying colleague B may be quite late, colleague A said its better to stick to the current arrangement. Unless both of us not around, then she will run. Ok la maybe she is a manager, dun want to do such things for us if need be, but I still dun see the logic coz its not like I asking her to run everyday...

Ended up colleague B was going to be late as expected. In fact, he said he got awaken by my sms so I LL got no choice but to wake up and run the job remotely.