Otherwise you would have created a net magnetic charge, which is a no-no.

This has the additional benefit of explaining why magnetic charge can not be isolated.

Crawling, he worked his way back and spotted a magnetic charge.

All items are recognised as having some form of electrical and magnetic charge.

That is to say, we can maintain the form of Maxwell's equations and still have magnetic charges.

What are the units in which magnetic charge would be quantized?

No total "magnetic charge" can build up in any point in space.

So far as we know, there are no corresponding atoms of magnetic charge.

Although the magnetic charges do not exist, it can be useful to think of them in this way.

If you take the batteries out of your remote, it will likely retain a small magnetic charge.