The more you learn about personal finance, the more complicated your questions are likely to get. But never fear: Hosts Robert Brokamp and Alison Southwick named their podcast Motley Fool Answers for a reason, and the Oct. 29 episode -- the monthly mailbag show -- the co hosts will tackle a whole bunch of money conundrums with a bit of help from Motley Fool Wealth Management Director of Financial Planning Megan Brinsfield, CPA, CFP, and all-around fine human being.

In this segment, they reply to an email from Isaac, who is considering taking advantage of a less-offered -- and even less utilized -- option in his 401(k) plan: a self-directed brokerage account. Break it down, and it's precisely what it sounds like: a sub-account within the 401(k) in which you can invest in whatever stocks, funds, and ETFs you choose -- regardless of the formal picks your company made for you to choose among. But if that's so great, why don't more people take advantage of it? Should they? The Fools have a number of thoughts on the topic. 

To catch full episodes of all The Motley Fool's free podcasts, check out our podcast center. To get started investing, check out our quick-start guide to investing in stocks. A full transcript follows the video.

This video was recorded on Oct. 29, 2019.

Alison Southwick: The next question comes from Isaac. "I recently discovered and opened an account through my 401(k) called a 'self-directed brokerage account.' My main reason for doing this was to expand my investing options due to the plan being very limited in what it offers. Could you please provide your knowledge and perspective on these accounts and the pros and cons regarding them? I feel as though very few people know they exist. In fact, when I asked my HR department about this option, they had no clue what I was talking about." Oh, Isaac!

Robert Brokamp: Well, one reason why people don't know they exist is most people don't have the option. Depending on what source you look at, anywhere from 20%-40% of 401(k)s have this side brokerage account. We have it, here, at The Motley Fool. And even of those that do have them, most people don't take advantage of them. So at Vanguard, for example, about 20% of the plans have the self-directed option, but only 1% of the assets are in the side-brokerage account, so most people are not taking advantage of them. 

And it doesn't surprise me that the HR person didn't know this. I love HR people. They're wonderful people, but they're not necessarily the best expert about your plan. That's not true, here, at The Motley Fool, in case any of our HR folks are listening, but my experience interacting with HR folks is they don't always know the details of their plans, so it's often better to contact the financial service provider of your plan to ask the real nitty-gritty details.

Why would you do this? Thousands and thousands of investment options. Once you go to the side brokerage account you can buy any stock, any bond, just about any mutual fund, any ETF. If you are an educated investor and you're comfortable with that flexibility, go right ahead. There might be some extra costs involved. Maybe an annual account fee. The Motley Fool plan used to charge an extra five basis points. Now The Fool covers that, but just be aware of any additional costs.

From the 401(k) provider side, why don't more plans do this? Well, a lot of 401(k)s feel like this isn't a good idea for most employees. They feel like giving them that much freedom is basically too much rope to hang yourself with. Hopefully if you are going to do this, you are a knowledgeable investor, a good Fool, and you won't do too much active trading or anything too crazy in your 401(k). 

Megan Brinsfield: And the employer, to some extent, is on the hook for the decisions that they make available to you, so having too much rope to hang you with; you, as an employee, in theory, let's say you take the rope. This is a horrible analogy, but you take the rope, you do the trades and you mess up. Then you're like, "Actually, employer, you shouldn't have let me do that. You should have known better." There is a possible course of action, there, because the employer, as a 401(k) provider, has to be making sure that the boundaries are set up appropriately for the participant. It's not like a slam dunk.

Brokamp: That's why most plans don't offer it, because the 401(k) providers don't want to take on that potential liability.