Can also be situation, location, connection with other SPs. I am in a geographical area in which most SPs keep to themselves for privacy reasons, and or is frequented by tourers. Also I when I have recommended on the basis of knowing an SP, usually via forums and the occasional social in-person meeting, the SP and punter did not click, the first time this happened I ended up as go-between in the aftermath eg "Why hasn't he left me a report, I know he is a report writer", "Umm didn't go as expected"...was really difficult. Sometimes I am asked for contact details but they are not publically displayed, and I do not have them anyway.
Total agreement here
Also like Strawberry I'm in an out of the way area, in my county there are probably 30 regular SPs, so it's unlikely that I could recommend someone that my client had not already checked out on aw and decided against for various reasons.
I don't see those SPs as rivals as they are all different to me but a also don't recommend any of them because I have no idea what their services are like.
I've had guys contact me telling me so and so recommended me and one guy who said he had been discussing me with another local escort and she had said he should try me, I refused the booking for discretionary reasons, he couldn't understand why.