The 5 absolute worst ways to earn passive income, according to a 6-figure entrepreneur who's tried dozens of them

• Jen Glantz is an entrepreneur who's tried various side hustles to pass time and make money.
• Some have paid off, but a few of them have cost her more money than she made in the long run.

When I was laid off from my full-time job in 2015, I promised myself I'd do everything I could to never work for a company again. I didn't like having a boss or a nine-to-five schedule. I also wanted to finally make six figures, and I knew the way to do it was to pursue multiple income streams.

Since I was a solopreneur who didn't want to work 80 hours a week, I knew some of those income streams would have to be passive, meaning they'd require little or no effort to maintain.

I tried out dozens of passive-income streams, from renting out my stuff to selling online courses. While some have been rewarding and helped me hit my six-figure income goal, others have been a waste of time and money.

From my experience over the past eight years, here are the five passive-income streams I wish I never tried.

1. Selling products

After getting married, I created a card game for newlyweds. I spent around 20 hours writing the cards and designing them for free using templates on Canva. I made a landing page on an existing website I had, where I was already selling books and merchandise and was generating traffic every month.

I invested around $1,000 in the production of 75 units, using a company to print, package, and mail the games to me. I planned to sell them for $18 each.

Once the games arrived, I planned to spend a couple hours a week marketing the card games on social media and in my newsletters, and around 10 minutes weekly mailing out orders.

I quickly learned that selling your products takes more time and money than anticipated.

After investing that initial $1,000, it took me five to 10 hours a week at first to try to sell the game, and in the first few months, I sold less than half of my inventory. It took six months to sell all of it.

I wish I didn't pay for inventory upfront, especially when I wasn't sure how much of the product I could sell. It would've been better to go with a print-on-demand option, like Printful, where products are made and shipped only after sold.

I ended up making a little profit from the game, but it wasn't enough to view this stream of income as a success.

2. Investing in individual stocks

During the pandemic, I decided to invest in the stock market for the first time in my life. Before that, I was very cautious about where I put my money. Some of it went into a retirement fund — an SEP IRA — and I put the rest in a high-yield savings account and interest-yielding certificate of deposit, where I earned passive income at varying rates.

But in 2020, I gave in to pressure from friends who were constantly telling me about the stocks they were investing in and how much money they were making. Without doing any research, I opened up an account with a commission-free investing platform and bought stock in random companies that I liked or thought were interesting. I didn't study market trends or even put more than a few seconds of thought behind which stocks I bought.

At first, I was making passive income as the stocks increased in value, and I sold off a few shares to make a profit. But as the months went by, I lost money not selling shares in time or hoping that prices would rise, when they ended up just getting lower.

I've lost almost $6,000 in total. Trying to make passive income in the stock market is risky, especially when you're someone who doesn't fully understand it.

I would've been better off researching companies and investing in dividend-paying index funds, which are a group of stocks that pay their company earnings to shareholders.

3. Flipping products

Five years ago, my partner and I decided to find a passive-income stream that we could tackle together. He had experience flipping products on eBay and making money as a reseller. This time, we decided to try to flip concert tickets.

We spent 30 days buying tickets at face value for popular concerts by artists we were familiar with as soon as they went on sale. Then we relisted them on resale sites like StubHub and SeatGeek for double the price.

There were some concerts where making a profit on the tickets was easy. But for the most part, we had to spend three to four hours a week monitoring the resale sites to stay competitive with our pricing, so we could flip the ticket before the show.

About 50% of the time, we barely broke even, and occasionally, we lost money because we weren't able to resell the ticket. The other 50% of the time, we were able to break even and earn money.

In the end, this passive income stream proved to be stressful, time-consuming, and risky. It wasn't a sustainable way to make money, and the amount of effort that went into the process didn't make it worthwhile.

4. Running ads

Three years ago, I decided to try running ads on a blog I had been operating for a few months. I signed up for a Google Adsense account, which helps you run ads on your website, and connected my blog. Anyone who owns a website can try this out if you meet Google's criteria.

You earn income based on how many clicks and impressions you drive to the ad on your site, and the amount varies. Since my website traffic for the blog was less than 1,000 views a month, I was only earning a few dollars running these ads.

If I wanted to optimize my earnings through these ads, I'd have to invest in getting more traffic, which would require additional time spent marketing the blog, doing search-engine optimization, and even spending money on Google and Facebook ads to get the URL in front of more people.

Since I'd have to dedicate around 10 to 15 hours a week and invest a few thousand dollars in working with an SEO expert and running those ads to get traffic, it could take me a very long time to generate substantial passive income.

This source of income is only viable if you have heavy recurring website traffic or want to spend time and money growing the website. In my case, it wasn't worth the time or effort.

5. Earning cash through credit-card bonuses

When I was first laid off, I decided to try to earn as much cash as I could through credit-card bonuses. This was one of the worst ideas I had to make passive income, because it required me to open up different card cards that were offering major bonuses if I made enough purchases in the first few months to meet the spending requirements — for example, one card offered 80,000 bonus points if I spent $2,500 in the first three months.

Since I was cash negative during those first few months, I relied on my credit cards to make a lot of must-have purchases. After earning those bonus points, I redeemed them for cash or statement credits, and called that passive income.

While I'd earn a few hundred dollars per credit card in statement credits, the process left me with a few open credit cards that I hardly used after I received the bonuses, and debt that took me a few years to pay off. It also negatively impacted my credit score, since I closed two of the credit cards I hadn't used in years.