Expensive, accurate and a dying breed.
CRT (Cathode Ray Tube) monitors have been around since the dawn of television. That’s a long time to perfect a technology. In many respects CRTs are still considered the best display devices around.
There are many things that go against CRTs. They are expensive to manufacture. They are very heavy and consume lots of energy. The light emitting phosphorous coating on the inside of the tube fades with time rendering monitor out of spec after years of use. The phosphorous also fades faster in the areas that are constantly lit up creating a burned ghost image.
Screen savers that incorporate random movement will protect your monitor from burnout.With proper calibration and color profiling CRTs are extremely color accurate but will change over time and require frequent profiling/calibration. The accuracy alone is the biggest reason CRTs are still around although the monitor manufacturers are abandoning this technology.