737 Pre-stall buffet at high altitude. Not at landing config low alt. Why?

[rudderrudderrat]

Hi Tee Emm,

Have a look at "Stick Shaker" explanation Aero 12 - Angle of Attack
"The early stall warning system thresholds were not set to be effective at cruise altitudes and speeds because they did not correct for Mach number (fig. 10). This kept the system simple. The stick shaker was set at an AOA effective for low altitudes but at too high a value for cruise. Natural stall buffet was found to give satisfactory warning at higher Mach numbers."