If someone recommended it to me and the service was not good, I let them know.
If I have very poor service, I ensure that people thinking of using that service know. I also will put in a complaint if needed.
If the service is bland, I say nothing but generally don't return or recommend. I like good service, but mediocre service isn't something to complain about.
Example: shop where assistants (young and unsupervised usually) are more concerned about their night out than service and so do not do a good job. I stay away and would not recommend. Meal out where it's a little too full with too few waiters, then I don't put it on my list of places to return, but would try again if others wished to go there. Health "care" we've had in hospitals in the last 10 years... that's very poor and people do know about that! Although they do nothing about my complaints.
Also I find where I live I need to be careful what I say and how I say it with regards to businesses. Too small an area where I live and it is really 2 degrees of separation if not less between everyone. So, it can be very easy to get people off side if their friend, mother, SIL, BIL, 2nd cousin is the person or the business owner I am talking about.
So I can't go "Blah business is rubbish", I need to be clear "I received poor service on xxxxx date, I found the assistant lacked knowledge in the area of xxxx". Basically what ever I say has to be well thought out and polite, otherwise too many enemies can be made.
I generally speak up at the time if I am unhappy with a product or service. If the issue is rectified, no problem. If it's not rectified I am a namer and shamer.
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