I had my hair lightened early last year from a dark plum so it would be more like my natural colour for our wedding (with a bit of a sunkissed tone thrown in).
After just one session of highlights, my hair was rediculously different to when I had sat down, so much so even the hairdresser was amazed. I had gone from plum to sunkissed brunette in just a couple of hours.
Therefore, I only needed it done one more time just before getting married so that I didn't have any roots. Since then (last September) I haven't had it coloured again mainly because after having damaged my hair with bleach years ago, I didn't want anymore put in (or for my hair to get any lighter). So, of course my roots have grown through.
However, my hairdresser friend told me when I last saw her that grown out colour or a 'drop root' is actually in fashion at the moment which I must admit, I have since noticed on several celebs including Caroline Flack and Rachel Bilson.
Wow! Being lazy pays off sometimes it seems....not maintaining my hair has resulted in me having an up to date hair do without even trying.