At what ring count do you stop the phone from going to voicemail and why?

Most phone systems let you pick how many rings before the call rolls to voicemail, and the choice you make quietly decides whether an inbound lead turns into a job or a voicemail you may never get back to. How many rings does your business line do before it sends the caller to voicemail, and why did you pick that number? Do you run fewer rings when your crew is on jobs and more rings at quiet times, or do you leave it fixed all day? Have you actually noticed a difference in how many people leave a message and how many of those turn into real callbacks when you change the ring count up or down?