Question

imagine that a tradesperson or worker disregarded your instructions for their part of the project. how would you respond?

Answer 1

In this context you don't need to get emotional.

First avoid drawing conclusion keeping in mind that there could be a valid reason.

After calming down you can summon the person who is concerned.

Try to find out why they disobeyed your order.

As they speak try to see whether their reason is genuine enough.

If it was intentional, express your disappointment politely and give a warning in order to give him another chance.

If you were the one who failed to give instructions clearly you should apologize and purpose to do it better next time.