First, I'd like to mention that our fellow writer Ralph Schwartz has recently published a fantastic hub on this very topic. I recommend everyone read it for the best, most realistic & detailed information on the minimum wage debate/discussion.
It's not really a matter of bad or good. It's economics, the hard core facts of being a business owner & the issues of profits & losses. Should the $15.00 minimum wage become law, thus making it mandatory employers pay this amount per hour to each & every employee, this is when the basic facts will become quite apparent.
Business owners will most assuredly hire "fewer" individuals, meaning the work load increases per employee. More often than not the prices of goods & services will increase, leading to the possibility of a drop in customer base & increase. What needs to be fully understood is that businesses exist to profit. If expenses increase, something & someone is sacrificed in order to achieve profit. This is IT, in a nutshell.
Again, I suggest you read Ralph's excellent Hub.