As Maggi mentioned, using a DA or rotary polisher with a pad/compound combination with any cutting properties should only be done as required
Your only removing a micron or two for removing most of the light swirls, but removing deeper scratches is really unknown territory until you get started. Without a paint thickness gauge to monitor the paint removed, you could easily end up destroying the integrity of the clear coat if you go for 100% correction on a regular clean.
Typical paint on a modern car is 100-150 micron, with this being roughly primer/colour making up 50% and the clear top coat making up the other 50%. So you may have about 50-60 micron of clear coat, unless it has previously been polished to death. Saving a good margin to keep the integrity of the clear coat and allow for variation in the thickness, you could have 20-30 micron to play with.
Glazing applied with a DA on a finishing pad may be a little better than by hand with a suitable applicator, but theres probably few people that can tell the difference.