That's not completely true. They haven't pulled my record since 1999. Since then I've hit someone in a parking lot, received at least 6-8 speeding tickets, made a million and one changes to my policies, including adding new vehicles, selling old ones, changing coverage on those vehicles, adding glass coverage, claiming a new window in my truck, new windshield in my old car... They still haven't pulled my record, and I guess they never will until I cause a serious accident. I have 4 vehicles insured with them now. In the last 3 years, 3 of those vehicles have been changed out.
I'm not sure what triggers it, but it's not necessarily a policy change (if they've never pulled it before). But they DO pull it for drivers who they regularly pull records for. I've been with State Farm wince I was 16, so they know my entire history. I'm not a risk to them.