The safe use current of LED lamps is generally 20 milliamps. Above this value, although the brightness will increase a little, the color attenuation will significantly accelerate. Therefore, when purchasing an assembled LED module, you must test its output current value. Brightness below 20 milliamps is not enough, and more than 22 milliamps affects LED life and accelerates color decay.
Please read the originial post here: https://agriculture-benin.com/technology-led-display-luminous-words-common-problems-and-solutions/