I love Japanese Maples, and this one in my garden is a favourite. I had bought a plant that after a few years died, but its root stock started to put out new growths, and the resulting plant was nothing like the one I had originally planted. However, because of its lovely leaves, and autumn colour it has remained and has got quite large. So large in fact we are slowly removing its main trunks and the effect of the cutting back, has encouraged new growths, again from its base. It obviously likes where it is (too close to the house really) and at some point it will have to be totally removed. However, the good news is that it sets seeds, and I have some lovely smaller versions growing on in pots!
