In many startup product companies, the specific knowledge about the product is not interchangeable with other tech companies. The tech skills and the soft skill

In many startup product companies, the specific knowledge about the product is not interchangeable with other tech companies. The tech skills and the soft skills are, but a large part is know-how about the product and the market. It makes sense to stick around longer if you see yourself as a "knowledge worker" rather than as an interchangeable techie. It certainly makes sense from the company's perspective to keep knowledgeable people around.