Usefulness is defined by Merriam-Webster as the quality of having utility and especially practical worth or applicability.
I have a strong appetite for business and hence usefulness because I believe everyone has self-worth that can be shared with others.

Usefulness depends upon subjective taste and personal goals. I attain business goals through my three professional services: writing, videography and illustrations.

I consider myself an expert in multimedia and talented in creative content, however not everyone is appreciative of my work. Picasso wasn’t fully embraced by the art world until after his death. Not everyone loves the writing of Rudyard Kipling or J.K Rowling. Some of Steven Spielberg’s films were panned.
Something that may be "useful" to you may not be perceived as such by somebody else. Therefore, the specific criteria that determine an object’s usefulness remain elusive and relative.

That doesn’t mean that business is irrelevant. With practice, anyone’s products or services will be appreciated by many as you build up a following.

Many products are universally useful. A clock's usefulness is to tell time. A stove's usefulness is to cook food. A jacket's usefulness is to keep warm. A broom's usefulness is to sweep floors. A vacuum's usefulness is to clean floors.

Some people prefer a cheap watch, others an expensive Rolex. It depends on their goals and tastes.
Business will always be challenging. It is this excitement for a challenge that I thrive. The more complex the project, the more excited I feel about the final product.