Can you count?

One of the reasons we chose our condo is the 24hours security system.
From 9:00am to 6:00pm, caretakers are stationed at the security office, and security guards are there and patrol in the condo other time.

Another reason is having nice facilities. We have a gym, party room, Japanese tea ceremony room, theater room, and guest rooms.
However, since we moved, we have never used them!
So, my hubby and I planned to use the theater room this weekend.

We needed to book the room. I went to the security office to fill in the application form after my work. That was obviously after 6:00pm, so a guard was there.
I filled in the form, and got home.

A half hour later, I got a call from the guard. The below is the conversation between us. G is the guard, and K is me, Keiko.

G: "Hello. You booked a theater room, but I said three hours is the maximum for using it."
K: " Yes, you said so. So, I booked from 7:00pm to 10:00 pm."
G: "It's FOUR hours!"
K: "Excuse me? I said, from 7:00 to 10:00."
G: "Right, 7 is one hour, 8 is two hours, 9 is three hours, and 10 is four hours."
K: "... Well, listen. At 7, I will start to watch a movie, at 8, one hour passes, at 9, two hours pass, and at 10, three hours pass. You got it?"
G: "What??? I'm confused..."
K: "OK sir, try it. Subtract 7 from 10. What is the answer?"
G: " Let's see... THREE???"
K:" Good! Now you got it, right?"
G: " I see! I am sorry!!"

...Can you believe it??? I live in a nice condo, but how can they hire such a mathematically-challenged guy??? (God, I'm kind enough to use a political correctness word!!)
...Maybe it's OK cause he made my day to give me a material for the blog...