Would you feel a bit cheated if you asked an electrician to carry out an inspection and he sent someone else?

I can't help feeling miffed about this. I asked a specific electrician to come and carry out a periodic inspection of the electrics at home, based on the fact that I had seen his workmanship, and we had a common acquaintance who seemed to get on with him.

We agreed he would come and do the work at a particular time and date.

Without warning, on the day, someone else turns up, says he works for him. I let him get on with it (wish I hadn't as he didn't seem very knowledgeable to be frank), and hopefully he did the tests alright (albeit his test tools were, by his own admission, slightly knackered).

I can't help thinking it was a bit off that I pay for one person, and get another person entirely.

Of course, this is probably a feeling based on my opinion of the bloke who DID show up, but do other people feel it is bad to accept a job as a person and then send some other random guy? Would I have been justified in telling the substitute 'no idea who you are, please don't come in' ???