Dangers of Electronic Keyboards
The difference between electronic keyboards and acoustic pianos is as follows.
1. More Expensive
Each key in an electronic keyboard turns on a sound recording for a certain note. The key is an on-switch. Then when the key is released, there is a turn-off switch that turns off the recording. Also, when keys are pressed hard or soft, they make louder or softer sounds. Electronic keyboards use different recordings for higher and lower volumes. So each key has several switches. There are a lot of switches turning on and off in electronic keyboards. But the worst part is that these are mechanical mechanisms that interact with electronics. That's a lot of interaction between mechanical and electronic equipment in electronic keyboards.
This is not the same as when you play a CD in a CD player. A CD player turns on at the beginning of a recording, and turns off at the end. In a CD, there is a block of sounds all sealed together, and there is only one on switch at the beginning of the block, and an off switch at the end of the block.
So keyboards tend to break down because of all the on-off switches interacting between mechanical and electronic equipment. When keyboards break down, you need to find an electronics technician who specializes in this type of equipment. A regular electronics tech cannot handle this equipment. This is a very specialized electronics tech. Then the tech needs to determine how to repair the equipment, order parts, and then install the parts. In short, the repair bill is often $400.
2. Motivation Killer
Electronics dealers like to advertise that their keyboards sound just as well as a piano. This is not true. Electronic keyboards have not been able to equal the sound of a piano.
Poor sound is a motivation killer for music students. Because piano students need to put a lot of effort into their studies, and are not getting proper beauty of sound motivation to keep them working.
3. Hand Damage
Acoustic piano keys have surface resistance which allows the non-playing fingers to rest lightly on top of the keys. This allows the hand to relax.
In electronic keyboards the keys just sink, so the nonplaying fingers cannot be allowed to rest lightly on top of the keys. So the hand needs to be always contracted in electronic keyboards. Keeping the hand contracted during repeated practice periods causes carpal tunnel syndrome.
By Lillian Simmons, Piano Teacher
And here's a good video about keyboards versus pianos: The battle of the boards.