My spouse has a cheap Craftsman non-sliding compound miter saw with a built-in laser. Lasers seem like such a good idea in theory, but they don't work as well in practice. We removed the laser batteries from the miter saw years ago, to prevent them from leaking. Lasers on miter saws are nearly useless. Few miter saws have two lasers, so most can show only one side of the cut.
We do the same thing as
@NoThankyou: Bring the unpowered blade down to line up the work with the carbide teeth, raise the blade, turn on the saw, make the cut. The blade tells the true story about what will happen, not the laser. The method is both fast and accurate. Who needs a laser?
Yesterday I spent an hour chopping wood on the miter saw. I used a measured stick to line up the cuts. I held the unpowered blade down, pressed the stick against the right side of the teeth in the blade, matched the ends on the right side of the saw, removed the stick, made the cut. Repeat. The last cut on each board was made in reverse using the left side of the blade, so I could hold the longer work piece against the fence with my left hand while chopping off the small remaining waste on the right side. The laser on our saw could have been lined up for the right side cuts or the left side cut, but not both at the same time. I suppose that some people line up the laser in the middle of the blade and adjust in their head.
Allow me to remind everyone to check and adjust their miter saws for accuracy. I tend to pay more attention to the table saw and neglect the miter saw. The table saw stays good, but the cheap miter saw goes inaccurate when it sits, parked.