Almost certain is a different thing

Two removal companies quote to move a family across Doha.

The first says nothing will break. Guaranteed. The second says that in most moves they break nothing, and when something does go wrong, this is what they do about it.

The first sounds better on the phone. It is also the one to worry about, because it has made a promise no removal company can keep. Somewhere in a houseful of boxes there is a glass that will crack, and on the day it does, the guarantee turns out to have been a sales line. The family does not only lose a glass. They lose the ability to believe anything else the company told them.

"Very likely" and "certain" sound like neighbours. They are not even on the same scale. Likely is a statement about odds. Certain is a promise that the odds do not apply. Present one as the other, and the first exception becomes a lie told in advance.

The second company has left itself a little room, and that room is exactly what makes it believable. When they say the van will arrive at nine, the family plans around nine. When they say the piano needs a specialist, the family pays for one without arguing.

The same habit serves every seller and every forecast. Say what is likely as likely, and mean it.

And when something really is certain, say that plainly too. Hedging a sure thing is its own way of losing trust.