Everything you need to know about vinyl turntables, all your Disc Jockey questions answered. Part 1
Why are belt driven turntables so much cheaper than direct drive turntables. Is this a gimmick or a scam?
TLDR: Short answer is, you can DJ on both but the direct drive is better if you can afford it.
The belt-driven turntable uses a rubber belt to drive the turntable and can be less consistent than the direct-drive turntables, that use a magnetic driver that is directly coupled to the spinning DJ platter.
What does this mean for me when I’m mixing you ask. The biggest difference is the speed and steadiness that the vinyl platter can get to the normal rotation.
There can be more mechanical noise on a belt-driven turntable (although it's practically negligible), but these days it does not make a massive difference and it has more to do with what you can afford.
The belt drive can wear and tear after a while, affected by heat and friction. The belt-driven TTBLS sometimes uses a gear system to change between the rotation speed of 33.3 and 45 (Revolutions Per Minute) RPM.
With a belt-driven turntable, if you take off the platter for a service, you need to release the tension of the belt before removing the platter.
Here is time tested explanation from Ellaskins (the Original DJ Tutor)