Kidney is the most important and most largest organ present in human body and kidney is considered just like the shape of a Bean that we eat as a very healthy food and as beans are important for our health so in a same way kidneys are more important for maintaining a good health.
A very basic understanding about kidney is that they are the organs that are important for purification of body from different waste materials so if there would be removal of purification system from body then all waste remain in body which would be fatal for body in return.
Water is very important for survival of life and it is set that a normal person should drink minimum of 8 glasses and maximum of 12 glasses and it is set that kidney work more properly when body have enough water so there is nothing wrong in it that's why water is highly recommended if you want to keep your kidneys healthy.
Kidney example in relation to water is just like a machine that if a machine is not in use then definitely after sometime machine would start to destroy so in the same way if kidneys don't have enough water then waste materials would not purify from body and from kidney that's why kidney function could be hinder.
There is a need to keep kidneys healthy because a person can survive with one kidney but cannot survive with two kidneys so its very important to take care of yourself otherwise their can be different complications regarding kidney health that I am discussing further.
Regarding kidney health there can be different complications like if a person don't take care of electrolytes and proper salts that he is taking from his diet then definitely there can be salt deposits in the form of calcium potassium or other salts and it may convert into stones and stones maybe complicated for kidney if they are in larger size.
If creatinine levels increase in body then it can be very harmful for kidney because it may not let the kidneys to purify in a proper way and to function in a proper way so ultimately failure may also occur if it becomes more complicated and then can be sort out with dialysis but not for a longer time.