I have no idea where you work, but in my career experience, telling my bosses to take a running jump would see me very quickly in the line for a government unemployment benefit cheque.
Therefore the statement is valid.
Likewise:
“tinkicker, how long before you get that excavator up and running”?
Thinks. Hmm 4 hours… I’ll add on 50% for unexpected ocurrences…
“Err somewhere around 6 hours I would guess”.
Gets it started after 4 hours, great. Hang on a mo, it will not move. Ahh ■■■■ the hydraulic pump has burned out too and its going to take 8 hrs to change.
So my time quote to repair has doubled, despite my being on the conservative side. These things happen.
Saying " they should have had it ready" just does not work in real life. Excrement happens.