No one strives to be dispensable at work. Most people want to be valuable and contribute effectively. There is a big difference, however, between doing a decent job and being an invaluable A-player.

It's sad to say that many employees fall short of expectations. Not because they do a bad job, but perhaps because the boss's expectations are so high. People are generally hired on the basis of their potential, and only a small percentage actually meet or exceed the ideal.

Most successful companies have at least one or two employees that rise above the set standard and would create a vacuum if ever they leave. Here are the traits that make them indispensable.

1. They are natural researchers.

Nobody has all the answers. Extremely valuable employees never let ignorance stand in the way of progress. When information is lacking, they will do their homework and readily share resources.

2. Their ego is the lowest priority.

Feelings and insecurities are important, but they can get in the way if placed front and center. Extremely valuable employees know who they are and know they are responsible for their own experiences. Their ego is never a source of disruptive drama.

3. They consistently inspire everyone else.

The CEO can't be the only evangelist and inspiration for the company. Employees need to see that success happens on multiple levels. Extremely valuable employees uplift everyone else and help everyone increase their performance and improve their morale.

4. They can teach anything.

Companies grow and personnel changes. Creating training programs is important, but sometimes someone just has to get a newbie up to speed. Extremely valuable employees can deconstruct any process and help others learn to perform it quickly.

5. They are all about efficiency.

Some people take on a task and work just to get it done. Extremely valuable employees know that any job worth doing is worth doing faster and easier the next time. They document their process on any task or problem and figure out how to make it simpler every time.

6. They happily assume any role at any time.

Business is a constant flow of change and managing resources. Instead of getting caught in the upheaval, extremely valuable employees dig in and act as utility players filling the necessary gaps regardless of their position, and they do it without letting their own responsibilities suffer.

7. They solve problems before they become disasters.

People buried nose-deep in their own issues are likely to get hit in the beak with unpleasant surprises. Extremely valuable employees always have a forward-looking, big picture view so that they can anticipate issues in advance and create solutions that streamline and bulletproof any process.

8. They build a network, and use it.

People can only grow as far as the information and the support around them will allow. A limited education and network will produce limited results. Extremely valuable employees are able to tap into resources quickly and easily to solve any problem or create nearly any opportunity. You won't see just 62 people on their LinkedIn.

9. They can advocate effectively.

Many employees complain that they aren't heard, valued, or that their needs are never met. Sometimes it's because of poor management, but often it's because effective self-advocacy takes thought and effort, not just vocalizing ideas or complaints. Extremely valuable employees know how to consider the company's position and resources. They can present a viable and executable plan that makes sense and provides a win-win for everyone involved.

10. They believe honesty is the best policy.

Most employees do what they have to do to get along. Telling people the truth can be uncomfortable and cause conflict. Extremely valuable employees know that hidden truths eventually surface, and rarely in a positive, productive way. Without being unkind, honest employees help others see potentially damaging truth before bad things happen.

11. They come to work because they want to, not have to.