if you dont know to drive a car and jump on the steering wheel most likely u will be involved in a crash. u cannot undo it if that happens. hence those who have limited or no knowledge its better for them to hire a consultant rather than facing a refusal. prioritise what u want a negative outcome or save couple of hundred dollars. as far as vicky_0909 is concerned he is in Canada on student visa and am pretty sure he hired a consultant to get his visa done so what is the problem in hiring a consultant again. on indian passport its not easy to get visa to any country let alone canada .... that is how things are done here . it is always good to seek professional help.
A consultant filling out a form is not going to guarantee an approval and most consultants are not very knowledgeable. It is based on the persons assets, travel history, etc.