Three reasons I’ve heard why people who don’t like to drink water: 1) It doesn’t have a taste and if it does it’s stale or doesn’t taste good. 2) To get a drink you may need to stop what your doing and then later it makes you need to go to the bathroom. If your trying to get a project done or driving a long distance, this may seem too time consuming. 3) I’m not thirsty. It’s hard to remember to drink when you’re not thirsty or you might not realize you need water even though at least six glasses is recommended daily. I saw this and thought it was a great reminder of it’s importance. 
Mark doesn’t like to drink water and often forgets that he needs it anyway. I printed, laminated and put the above chart on his bathroom mirror as a reminder. Since water often makes him choke, I’ve found that if I squeeze half of a lemon or lime in his glass of water he can drink it better because it gives it a taste and then he actually enjoys it.
Another great chart.
Uniting Caregivers 