Here's our recommendation on how to make turning the dial simpler.
Start with having the ColorMunki Photo/Design or i1Studio spectrophotometer out of the pouch used for monitor profiling.
Set the ColorMunki device on its base (where the serial number and lamp opening are). Put your right hand on the top right corner of the device (have the "Swiss engineered by X-Rite" lettering facing you).
Take your left left hand and put your thumb on the textured ring facing you, and your forefinger on the textured ring on the back side of the device. Now I think you'll find the dial will turn much more easily.
In addition, by only touching the textured side rings, you will avoid the accidental pressing of the side button (the dished in button with the three dots). When you press this button, the software thinks you are trying to calibrate the device. That is the likely cause of you having to repeat the measurement process a number of times.
Once you've got the device calibrated, turn the dial back down to the 6 o'clock position and begin your measurements.