A DC voltage source develops 10 V DC at its output terminals. A DC current
source that you found at the flea market develops 10 A maximum when properly
loaded. Is the first device a high-resistance device, or a low-resistance one? How
about the second device?
The 1st device should be a low output resistance because you want to transfer all of the voltage to the load. The Thevenin equivalence of the 1st one is a voltage source in series with the output resistance. The second one is high output resistance to transfer the current to the load.
I think it will answer your questions. Also, voltages source are easier to make because most electronic sources behave like voltage sources so a bit of regulation
is needed to make them behave as good voltage sources. To make a current source
you must regulate the current of an electronics source -- this can make it more complicated.