Carl and Mike are two great friends. They grew up together and stay together a lot. They both LOVE the delicious turkish meal Kebab and eat it very often.
One day Carl comes to Mike with great news.
"A new fantastic kebab shop recently opened in town!", said Carl. "There are already a lot of kebab shops in town, why this should be so 'fantastic'?" thought Mike.
"Tell me more" said Mike.
"This is truly the best, Mike! The owner is the most renowned kebab chef of all time and they have a lot of wonderful ingredients and the place is great and is really cheap and..."
"Calm down!" shout Mike. "From what you say I think you've already been there".
"Yes" replied Carl. "And there is something more I have to tell you. This is no normal place. They have a lot of costumers and can't handle them all. They've come with a very peculiar solution for it".
"And it is?" asked Mike.
"Riddles."
"What? Riddles?"
"Yes. Every costumer, to enter the shop, has to answer a riddle in one minute. After the minute passes, if the answer is correct, the doors open and he can enter to eat. You just have to say the solution, that's it! Mine was really silly: 'If a brick weighs one kilogram plus half brick, how much does a brick weight?'"
"??
" quickly answered Mike. BONUS! Solve this!
"Exactly! You should really give it a try!"
Really curious Mike decided to go to the kebab shop the same evening.
Upon arrival Mike was faced with a big door with a television screen on it. It was written "PRESS THE BELL". Mike pressed it.
Very soon the riddle appeared. "WOW! So Carl wasn't lying after all!" he thought:
WHAT'S IT THAT MAKES POTATO IN MANDATORY AND PATIENCE IN CAT?
"...Wait, what? Mandatory potatoes? What's this? Think, think!"
The screen changed in a big 60 number. And started to countdown. 59, 58, 57..
"The cat is patient. Also the potato. No, no..."
...45, 44, 43..
"Argh! The time is flowing! ...Wait. I'm really struggling to solve a riddle just to eat a kebab? There is another shop just 400 mt from here. What I'm doing??" thought Mike.
...32, 31, 30...
"I'm not going to do this. I just want to eat."
"You know what? This is nonsense. There is a kebab shop just around the corner, I'm going there. Goodbye." shouted Mike, and left.
...10, 9, 8...
...3, 2, 1... CLICK! and the door opened.
Can you explain why?