Even if you tend to write with a heavy hand and create indents on the paper, the ink will erase so long as heat is able to reach it.

The erased sections can be written over and erased as many times as needed. Because of its heat-reacting properties, the ink may reappear when temperatures reach below -10 C (under 14 Fahrenheit).

It's best to not leave the ink out in hot cars or other conditions that may subject it to vigorous friction, or it may disappear.