Generally speaking, expertise can make an individual extremely valuable to an employer. However, expertise is often more difficult to match to a role than general and soft skills such as people skills.
A biologist who knows more about a particular type of fungus than anyone else on the planet.
A compliance expert who has a working knowledge of industry regulations and experience handling a number of major audits.
A contractor who has more experience constructing very large wooden structures than anyone else in their state.
A customer service representative who knows a great deal about hotel operations and the hospitality industry.
A hobbyist who knows much about kites and how to fly them in various conditions.
A pastry chef in Ohio who studied and worked in Paris for several years such that they have knowledge of French pâtissière methods.
A salesperson who understands a data analytics product well enough to answer obscure technical questions from customers without support from product engineering.
A sculptor who is good at welding.
A technologist who knows a great deal about the linux operating system.
An engineer who is an expert at modeling the strengths of advanced materials in stress scenarios for aviation.
An understanding of how ecommerce operations work.
Extensive experience fixing a particular brand of elevator.
Knowledge of the building codes in a particular city.
The ability to code and optimize code in a programming language.