This misconception that you have to buy one Bitcoin to own the coin is popular in my area. This is why most people see Bitcoiners as wealthy since they assume that they own one or more Bitcoins. This beliefs among these uninformed people has also made them lose the opportunity to invest in Bitcoin since they are waiting to get enough money to buy one Bitcoin.
By adopting DCA anybody can buy Bitcoin. Low or average income earners can set aside dispensable fund to buy Bitcoin consistently over a period of time. But it also important to set aside emergency funds before buying to avoid premature sales.
You don't have to own a whole coin but it's also a misconception that you can also accumulate Bitcoin by spending $10 per month. What do I mean; you'll often see newbies here (I also responded to a relevant thread a while ago) with a budget of $20 per month, to buy Bitcoin. In these individuals, it has been carved into their mind that Bitcoin is a quick get-rich-quick scheme in which their $20 will flourish. What I'm trying to say is that the DCA method is great, but only in cases there's a realistic budget, and not something as ridiculously low as $10 or $20, because we all know that such amounts won't lead to any significant returns.