One word: price. But if we want a second word: completeness!
TwoTrees is perhaps the best brand for anyone looking to save some money, but their machines are complete and powerful.
The model I tested is the flagship model, the TwoTrees TS2. Equipped with a 10W laser, with motorized Z axis slide and auto-focus, limit switches, drag chain, and predisposition for air-assist it has a lower cost than many other machines that do not have these options.
Not only that, it is a machine with a larger frame, which allows you to make engravings up to 45×45 in size.
Obviously this is a flagship machine (so it’s not the cheapest model) and it’s certainly a bit complex for beginners, but TwoTrees has a product line that is also suitable for beginners and those who don’t want to spend a lot.
TwoTrees TT-5.5S for example, is one of the cheapest engraver you can find. With less then 200$ you can have a full-working laser engraver with 5W optical power laser.
They also have machine with closed box and fume-extraction system for whose who need safety and usability inside closed places.