This article resonated on so many levels with my experience of running a small business. I wish I had seen it three years earlier :) A few additions from me:

1. Monthly subscriptions

I wanted for those to be a success so much. After struggling for a few months with churn we decided to stop them and only offer annual subscription. We had people subscribe for a month, (ab)use our customer support for the entire period and then cancel because the task that needed our product was done with our help. One could argue that our product doesn't bring enough value or that we made a mistake providing the support. We have a few times less churn from annual subscriptions and in general a lot better and happier customers.

The other thing with annual subscriptions is that you get your money upfront. Monthly subscribers churn for trivialities such as expired credit cards.

2. No investment

A big hell yeah on this one. We were this close (three times) to get investment money. God I am so happy we didn't. Our main goal was hiring top talent. Unfortunately the talent didn't turn out to be that top so we turned down the investors. The whole experience with building pitch decks made me disdain the investing process and the people involved. Now I think of investors (accelerators, angels, VC) as a waste of time. You are better spending that time on your customers and product. I know a lot of people on HN would disagree with this ;)

3. Grow marketing skills and don't pay for anybody to do it for you

Learn how to do marketing. Just do that. And by marketing I mean mostly content marketing. Learn how to write copy, learn how SEO works, check your Google search console often to see where you stand for the keywords that matter.

4. Ads

We don't do ads (Google, Twitter, Facebook). We tried it and failed. For example we were the top (only?) merchant bidding for particular keywords and still reached zero conversions (and paid Google and Twitter a lot of money). Facebook was even a bigger flop.

5. Accept only credit card online payments

Hell yeah! Issuing invoices, accepting wired payments and manually hooking up a "fake" subscription with your licensing software is a mess. God forbid somebody asks for a refund. I strongly back what the author said about Gumroad and Paddle (we use the former and are quite happy).

6. Promos

This was one of our biggest mistakes. Doing holiday (Christmas, end of year, black Friday, cyber Monday) promotions definitely brings some sales. In our case though almost all of those new customers (90%+) churned at the end of the billing period. We have less than 10% churn otherwise.

7. Discounts

We no longer do discounts for individual requests ("hey I like your product but it needs feature X - give me $100 off for the tip" or "I have a great idea I need your product for but can't afford it yet"). We decided we don't need that kind of people as customers. Always very demanding and the end most of them (70%+) churn. In the early days we did a lot of those though.

We still do volume discounts. Also we no longer do educational or non-profit discounts. Education institutions and non-profits often have bigger budgets than the rest of our customers. It isn't fair to make a discount for a huge non-profit and to charge regular Joe the shelf price.

8. Freemium

We do it, it sucks. Probably shouldn't have done it. It is a lot of effort as the author says. Can't really measure the conversion rate. Probably the only good use for it is the (somewhat) extended trial - we disable a few features of the product after the trial ends.

HTH