PSA's Evolving Role in the Hobby & the Future State of Grading Companies: PSA vs SGC vs BGS

PSA is growing at a rapid rate in the hobby. The company is evolving in ways that improve the overall experience for the customer, and now they're making it easier to sell your cards too! However, what does this mean for the future of SGC and BGS? You as the hobbyist can grade and sell your cards with PSA, so are people still going to want to send their cards to other grading companies?