Coarse, dense, fast-growing beard hair is common in India and it is the load that exposes weak machines. The failure is easy to recognise: instead of cutting on contact, the blade pushes the hair over, bends it, and catches it on a second attempt. That is the tug you feel, and it is also why your skin is irritated afterwards — you compensate by pressing harder, and pressure is what causes razor burn.
Motor speed is the specification that fixes it, and one brand leads clearly. Panasonic's linear drive runs at roughly 14,000 cycles per minute against Braun's approximately 10,000, and its blades are ground to a 30-degree nanopolished edge rather than a conventional profile. The result on dense hair is that it is sliced on contact rather than pushed. Owners moving to a Panasonic Arc5 from a mid-range rotary routinely report halving their shave time, which is a direct consequence of that specification rather than marketing.
For trimmers the equivalent feature is automatic motor-power adjustment. Philips' BeardSense on the MG9530 reads density 125 times a second and lifts motor speed on thick patches; the turbo mode on the MG7715 does the same manually. And the Panasonic ER-GB37 at ₹2,799 gets there through metallurgy instead, with 45-degree nanopolished Japanese blades that cut coarse hair more cleanly than anything else near its price.