maybe i can help you. I am not an expert tho!
LED's work with with a material which creates the color ( wavelength ). Like
@jingo mentioned alrdy the producing process will be aimed to be at the lowest cost possible.
To create a LED that emits for example the color red you can use different materials. So at the end the price and the quality of that material change the quality of the endproduct.
Next thing to keep in mind is that High-Power-LED's need to be cooled. Transfering heat through metal ( from the actual diode to the heatsink ) needs to be fast.
The faster it should be the more expensive it gets. The list goes from expensive to cheap: Gold, silver, copper, aluminium.
The warmer a LED gets to more power it needs to put out the same amount of light. So keeping them cool means keeping them more efficient.
The better a cooling system ( in terms of how much heat energy can be pulled away ) the more expensive it gets.
Also keep in mind that as long as both lights dont got the same LED ( in terms of wavelength/Color ) at the same place over the same coverage, you end up with a different light source.
So be sure if they are rly identically before you compare them.
So you can see where all of this leads to. If i combine all of this to your situation i end up with this: ( i just assume i dont know it for 100% sure )
I assume that both lights use the same driver ( so both draw the same from the wall ) and both lights look the same in terms of design/layout of the LED's and the light size at all.
The cheap light maybe has low price parts, bad cooling and old generation LED's.
The Mars maybe has more expensive parts, better cooling and maybe new generation LED's.
The spectrum of both lights will be slightly different. The draw from the wall is close to the same.
Most companies with more experience put a lot of money into testing, upgrading making things better or more efficient.
Maybe Mars got a better cooling design or even got a better electrical circuit ( in terms of security and LED's in series/parallel ) but be sure big companies tend to start using cheap parts as their business grows.
A thing to keep in mind is that from the light aspect itself the only difference would be a different spectrum and a different intensity but at the end both will do the job. ( the mars maybe more efficient than the "noName" product )
Check both light from time to time for defect LED's or unusual heat-spots.
