The company is a start up with no burning intent to ipo and sell off.
What this means is that you will get to wear many hats and climb in responsibility very fast meanwhile the company will care for you as an employee because of its private ownership.
Inconvénients
Expect to do a lot with little training. Often times you will be asked to do things that weren't in the job description. It'll give you a headache in the moment but a story down the line.
Salaries are not as competitive as larger companies or even more traditional fast paced start ups. Because of private ownership, there is no stock options or RSUs because there is no plan to ipo.