Yep, letting colored hair to grow is the bad part of the picture!
Since i stoped dying i no longer bother about this, and another good thing is that i can leave more time between cuts because it doesn´t damage as fast as it did before.
But i love dyied hair!!! I´m just going trough a fase in witch i like it in the original colour!
And whenever i feel bored, i just do a glossing, wich is basically colour that doesn´t change the original one, and doesn´t bleach the hair, so it washes after like 15 washes and voila, your natural colour again!