ip addressing question

Hi, in my job place there is a lan with an ip addressing like this:
(example)
address 10.0.0.1
subnet mask 255.255.255.0

in the lan there are only 40 pc and so I suggested to my CEO to use a private class c addressing like 192.168.10.1, but mysuggestion has been rejected?Why, in your opinion?Thank you in advance