Here's why:
* Subordinating conjunctions connect a dependent clause (a clause that can't stand alone as a sentence) to an independent clause (a clause that can stand alone).
* The phrase "Whether Jake or Jason has experience and talent" is a dependent clause because it doesn't make complete sense on its own.
* The phrase "is important though other qualities are expected too" is an independent clause because it can stand alone as a complete sentence.
* "Whether" connects these two clauses and shows the relationship between them.
Let me know if you'd like more examples of subordinating conjunctions!