It has been asked many times, but anyway...

I used to leave a little lace because it means when you comb back your hair or are styling it, there's more lace in front of the hair to stick down rather than pulling on the hair and it lifting the lace off my bond. But it was much harder to hide. If I was standing and someone was sitting and they looked up at my hairline, they might see a line if the lace wasn't all down perfectly.

So cutting right to the hair is what I do now and this gives a more natural appearance. At the expense of sometimes it lifts a bit when I'm styling my hair back.