Yes, this is not clickbait. Mailchimp has made a name for itself by offering a basic free email marketing system where you can start an email list. However, you'll find some problems with Mailchimp that could make you think twice before jumping in for that sweet sweet free account.
Deleted for affiliate links
First, they frown upon the use of affiliate marketing links in your emails. They will outright suspend or delete your account. They say they don't but there are many stories where accounts have been deleted without notice for this reason. They even have an article on their website trying to explain the difference between affiliate marketing links and affiliate links.
Yes, there are differences, but the line is so blurred, I wouldn't take a chance with Mailchimp. It's almost like they have that in their terms of service just to have a way to delete your account if they feel like they want to. Technically speaking, the definitions are clear, but practically speaking things can be confusing. An algorithm and some sort of filter will determine if your links are good or not. How do you decide beforehand? I don't know. Don't worry you're not the only one confused.
Mailchimp has this section in their "clarification" post:
Deleted for "inactivity"
This one is tricky because I can understand their point of view on this. If you don't use it, you lose it. Maybe they're doing it to save resources, or to keep some of their metrics up. I don't know exactly and frankly, I don't care to find out. But the bottom line is that if you don't use your free Mailchimp account often enough, they may just delete it outright. I just had this happen to a client.
My client had an email list with just over 1000 subscribers and they hadn't used it in a while. Despite the fact that the list was built slowly, over time, with subscribers looking for the content my client provided, using double-opt-in, Mailchimp decided that he hadn't used it often enough so they deleted it. No warning, no heads up. And he's not the only one, there are many stories about this happening, like this one, or this one.
Out of curiosity, I went to check on a list I had created for my daughter's website. It had a very low subscriber count, we built it just for fun. Most of the subscribers were just family and friends so I'm not too concerned. But that account too was deleted.
Apparently, Mailchimp wants you to spam your list regularly, send them stuff all the time, even if you don't have anything real to say. Go figure!
On one hand, they don't want you to use affiliate marketing links, but on the other hand, they want you to behave like an affiliate marketer by sending emails even when you don't have anything to send.
What's the alternative?
I believe the alternative is paying for your email list. Even if you start with a free account, think about it as a paid service and treat it like a paid service. I think if you pay for it, you'll have more skin in the game and you'll develop your list more and make a better effort to maintain it and use it.
Incoming shameless plug: my list is in Aweber, and I recommend that. They offer a free account as well, but they won't delete it and they won't delete it for using affiliate marketing links. Also, they will help you grow your list. I have used them since I started and they have always been great. Use my affiliate link to sign up with them.