Its like if you open any physical shop(To sell any products) you should get benifits!! of course if it runs good 
Same as you should create website into Magento in order to sell something. Basically Magento is readymate e-commerce solution, you just configure and host your site its done. Next you've to manage categories, products, shipping and payment for your site. And most important benifit is its Free (community edition). However for extra things may you need to spend your money as per your needs and requirnment. Cheers 
