A driver or current stabilizer for an LED is the same as a ballast for a lamp. It stabilizes the current flowing through the LED. But LEDs are powered not by voltage, but by current. Therefore, the lifespan of the LED crystal directly depends on the stability of the current value.
The light output of an LED is directly proportional to the current, and accordingly, the brightness of the LED turns out to be unstable depending on current fluctuations. If the current exceeds the permissible limit, the LED crystal will overheat and this can lead to accelerated aging - a drop in brightness and failure. Therefore, the current must be stabilized.
The stabilizer (driver) continuously maintains the current of each individual luminaire at the required level. It can be either built into the luminaire or directly on the board, or placed in the break of the low-voltage power line. Prices for luminaires without a current stabilization system are lower, but such devices will not last long.