It's better for an engineer to be an entrepreneur because an engineer has a good knowledge about technology and have a good skills in the field. And there is a lot of technical demand in today's society for the solutions of today's problems. So if you will do job then the knowledge you have acquired in your engineering will go in vain and at the same time it may happen, that the placement you are given or the job in which you are employed is for short term.
So to earn a long term profit you must start your own work. As an entrepreneur.