If you have shoulder length hair how often do you get it cut?

[username5555]

Thinking of getting my hair cut into a shoulder length bob. However the only thing putting me off is the possibility I will have to go to the hairdressers more. I currently have long hair and go to get it cut every 12 weeks. Been told it would be every 8 weeks with shorter hair.
Is this correct? Thanks

Also forgot to ask if anyone has had their hair cut from really long to short. Did you regret it? I've had it long all my life and really fancy a change but am quite nervous I will hate it.