This is because a good mentor will always try to bring out the best in a person looking up to him. So by doing that, a mentor won't allow you to get comfortable quickly, park in a better spot, take longer lunches nor avoid customers.
His role in your life is to make you a better version of himself which imply work and total commitment.
The person is still right because he said there was a sheep in his direction and there was just not the sheep he thought it was but a different sheep and he never said there is only 1 sheep like figure in that direction