By borrowing against your securities you have more cash to invest. You've put a multiplier on the amount you can invest. That's leverage. However, you have to p

By borrowing against your securities you have more cash to invest. You've put a multiplier on the amount you can invest. That's leverage. However, you have to pay back the loan with fees and interest. This increases risk because you could end up owing money rather than just having none if the securities crash.