Softswitching Advantages and Disadvantages?

Answer 1

I assume you are talking about a soft motor start where the speed of the motor is electronically ramped up to its starting speed....

Advantage: Low peak starting current draw, Gentle start of equipment. , Starter may incorporate Speed control and torque limits. (Check out Variable Frequency Drives VFD's)

Disadvantage: Delay in start up and attaining full speed. Difficult to use for starting motors which may be under a load.
Higher cost for the motor starter