Like a man, a lipstick and a car that works for you, when you've got a reliable hairdresser you tend to stick with them - after all you are building a relationship of trust (they have the scissors and strong chemicals!) as well as a commercial one (you pay them).
This bond can become more intimate as your relationship progresses over time so a fear of being disloyal is what makes it difficult for some clients to move to another salon.
So what would make you change your hairdresser?
Confidence - If you are starting a new job or relationship and look in the mirror and feel a lack of confidence maybe you need to change your hairdresser and get a great hairdo rather than what you've had for years.
Cost - Some salons are way more expensive than others, depending on their rents and their branding. Others may offer loyalty programmes, special offers etc. Your personal circumstances may change and you need to cut back on what you spend on your appearance.
Change of personnel - Often salons have a high turnover of staff especially large chains, so your stylish might have a) gone on maternity leave b) taken up a job abroad c) gone travelling with a boyfriend since your last appointment (and these have all happened to me). If you are offered a different member of staff then you might just as well look around for another salon.
Convenience - A new salon opening near your home/work/children's school so you can save time fitting in a hair appointment
Customer service - If you have been going to the same place for years and they still don't recognise you when you turn up it's time to ask whether you are getting the service you deserve. Was the scalp massage great before but now the junior hasn't been trained properly and cuts corners? If you then want to pop in for that promised free fringe trim and they can't make time for you ever it could be time to look around.
Wanting something different - A friend just went to Ascot and needed an up-do which she felt was a little beyond her normal hairdresser. So she went somewhere else that did a good job and would go to them for a similar reason. She'll stay with her normal stylish though for cut, blow dry and colour as they are much cheaper.
So if you've decided to look around how do you choose a new salon?