In Projects, Scaling up amplifies the bad and makes the good more difficult !!".what is your views ?

Well that would depend on the definition of scaling up really. Making 1000 left turn instead of 1 means that you are scaling up by doing more turns but since they are all the same it should make it easier, more predictable and less risky i.e reduce the 'bad'. But if you go from 1 left turn to 1000 random turns you increase the uncertainty, risk, and difficulty.

"Scaling up" a project could mean just making it larger or it could mean increasing complexity, these are not always the same thing. If you increase complexity then you increase risk (if this is what you means by 'bad') but that does not mean it will end bad. It just means you will have more things to focus on.