Drawing from margin prevents you from needing to sell and rebuy securities to free up $ as needed. This means no taxable events occur, so you don't have to deal

Drawing from margin prevents you from needing to sell and rebuy securities to free up $ as needed. This means no taxable events occur, so you don't have to deal with capital gains. It's also the cheapest possible credit you can obtain as a consumer. TBH it's so cheap that you can reasonably expect your investment returns to at least match it in the long run, so as long as you aren't drawing so heavily as to get an unhealthy leverage ratio