In most situations, I prefer to purchase online. I'm always provided with a wide variety of products, brands, and styles to choose from. Plus, if I'm unhappy with the selection, another store is just a click away. Being able to shop around provides a deeper comfort level with your purchase, and shopping online takes away the nagging sales person asking if there's anything they can do to help.
Unfortunately, there are many risks associated with purchasing online. You may run into a fraudulent store who simply wants to take your money and run. You may never receive the item purchased, or you may be shipped something entirely different than what was advertised. Maybe it was the wrong shade of blue, the fabric was the wrong type, or the size was misrepresented.
Having your item shipped to your door is very convenient, but there is an unfortunate side to this as well. Damaged goods, stolen packages, and wrong-address deliveries may have you stuck in a position where you can't get a refund.
If you DO get the item exactly as you purchased it, there's the risk that the customer support line is unable to process a refund if you change your mind. As each company's goal is to keep a sale, no matter the cost, they would much rather offer you an exchange before a refund. Products shipped are typically no longer able to be sold as a new item for a variety of reasons, and will have to be sold at a discounted price to the next buyer. Although companies have ways to make up for a return's profit loss, some companies don't even have that word in their vocabularies.
Online shopping is a great service, very convenient, and sometimes cost-saving, but be aware of the dangers and be ready to jump over any obstacles before purchasing online. Be knowledgeable about the company you're purchasing from before sending them a dime.