Unpredictable

We have hit our first major snag with our building project today.
I am not sure how it works but it goes something like…
our builder sub contracted a plumber who thought he could do the three boilers but despite thinking he could…
he couldn’t so that we now have no heating in the church or the hall.
He has “gone off” and our builders have now had to find another plumber or plumbers (not sure which) to finish the job.
Also the gas board were meant to send three different gas people: number one two three, but man two came before man one and therefore they couldn’t do the job!
I know have to handle the many people who understandably are upset about it.
They are not upset about the snag but rather the unpredicatability of it.
Funny thing, people can cope with change if they know it's coming.