This example doesn’t apply. You are converting units of two different quantities. The kilopascal is a pressure unit. The unit kg/cm^2 is NOT a pressure unit. To the best of my ability to come up with a quantity measured in kg/cm^2, I would have to postulate that it would be a density multiplied by a distance. Pressures are force divided by area. Kg is not a unit of force.
The reason you can propose to “convert” the units you do is that you are implicitly assuming that your conversion occurs on earth at mean sea level. Under that condition, you can speak of the gravitational force exerted upon a 1 kg mass. You then convert that 1 kg mass to the equivalent gravitational force. There is no reason whatsoever to think that this gravitational force must be a power of 10 when measured in newtons, and in fact it is not. Therefore, when you “convert” kg/cm^2 to kilopascals, introduction of this gravitational force results in the “conversion factor” not being a power of 10.
AFAIK, when converting from one metric unit to another metric unit that measures the same physical quantity, the conversion factor will always be a power of 10.
This is where science and engineering diverge. Trust me, people measure “pressure” with kg/cm^2 all the time. So, in the real world, like I said, people have to deal with messy complicated numbers.
That’s life.