Question

A broad and thick handle is preferred for a suitcase?

Answer 1

Its because the pressure will be low when the area is high. Therefore, a broad and thick handle exerts little pressure compared to a thin handle. 
Hope this helped!

Answer 2

a broad and thick handle is preferred for suitcase because broad and thick handle will have greater area so it will exert less pressure on our hands and we will easily able to hold the suitcase ( note pressure is directly proportional to1/ A
i.e.P =1/A