Overwatering can eventually lead to root rot, which causes the leaves to dry and die. It's a more common problem than underwatering, which produces the same symptoms. People seem to react to dry-looking leaves by thinking the plant needs more water, which is not always the case. Allow the soil to dry down to a depth of 1/2 inch between waterings. Dig your fingertip into the soil to test it for dryness.
Another possibility is that the plant is root bound and cannot absorb enough water from the soil to support the top growth. The top growth begins to turn brown and become dry. More water won't solve the problem. It just leads to root rot. So, is the plant still in the same pot it was in when you purchased it? If so, have you knocked it out of the pot to see if it's root bound and needs a larger container?
Never allow the plant to stand in water that has collected in its drainage saucer/tray.
Those are the most common causes of leaf tips drying, despite otherwise good care.
"Isn't it enough to see that a garden is beautiful without having to believe that there are fairies at the bottom of it too?" - Douglas Adams