A combination of demographic and societal factors is behind this: the aging of the population in most Western cultures; changing employment practices (does anyone retire at 65 with the proverbial gold watch anymore?); and the growth of entrepreneurial support organizations such as the U.S. Small Business Administration and the availability of inexpensive technology, making it easier than ever to start a business.
This is an important concept for any company that markets B-to-B to small businesses.
When you market to most small businesses you really are marketing to the small business owner. The owner is likely to be the primary decision maker for any sizable purchase. Increasingly, this owner is likely to be mature and seasoned. Contrast this with marketing to large corporations, where your message for the same product or service might be targeted to a (younger and less seasoned) middle manager who has equivalent purchasing authority.