Creating your own company from scratch is no easy feat, obviously. It takes a lot of hard work, perseverance, and yes, mistakes. It’s inevitable, especially for newbie entrepreneurs, to face challenges. But there are mistakes, and then there are mistakes. Those that you look back at years later and can pinpoint as the moment where “it all went wrong.” Whether you have your own growing business, or simply interested in startups, read on to see some of the absolute biggest mess-ups startups often make that end up costing them success in the long run:

Single Founder

This might sound like a simple idea, but it’s actually a crucial component to creating a successful business. Paul Graham, creator of Startup Mistakes, comments that when successful startups have more than one founder, it’s “unlikely to be a coincidence.” What are the problems with only one founder? For starters, it could hint at a lack of confidence in the project: no one wanted to go in business with you on your really good idea? Sounds doubtful. Also, starting your own company is simply too much work for one person; few companies can bare that load alone. Find a trusty business partner to walk by your side during your company’s start-up period.

Too Niche of a Market

Yes, you want to be original, to do something no one has ever done before. But you also want to have enough customers who know about, understand, and most importantly, will use your product. “If you make anything good, you’re going to have competitors, so you may as well face that,” Graham says. The only way to avoid competition is to not have a good idea. If you’ve thought of it, it’s likely someone else has, too. The key is execution. Do it better than everyone else, and don’t worry about the competition.

Launching to slow or too quick

Timing is everything. It’s hard to know for sure when to launch and when to delay. Spoiler alert: you might never feel ready. “Nothing is truly finished until it’s released,” Graham points out. Do you understand your product and its usefulness? Are you prepared to troubleshoot and adapt to consumer’s needs? Then you might be ready to launch. Have you launched and realized your company needs a complete redesign? Whoops, time to pull back and rethink strategy. The biggest danger in launching too quickly is reputation. A failure of a company can linger over an entrepreneur’s head for a long time. “Don’t expect a newly launched product to do everything; it just has to do something,” says Graham.

Not thinking like your customer

“Nearly all failure funnels through making something users don’t want.” It’s a powerful statement, and it’s completely true. What problem is your company solving? Is it a problem that truly needs solving? Will customers be thankful for your existence? Will they care? If an entrepreneur can’t completely answer all of these questions, then doom might be in the future. Knowing your customers means doing your research: find your target audience, understand them, and appeal to them.

Focusing too much on maximizing profits

So, you’ve thought about your customer, you have a widely-used product that seems to solve a problem, great. Now, you actually want to make some money, right? Of course! Making money is the easy part: there are plenty of ways to sell quickly and earn a buck. But if you’re in it for the long haul, it’s more than the sale: it’s making sure that people still want your product. This is much harder than making money. Don’t sacrifice a quick sales boost if it alienates any of your customer base. “It is irresponsible not to think about business models, but it’s ten times more irresponsible not to think about the product,” Graham cleverly puts it. Sometimes, it’s not all about the money. The best entrepreneurs understand they’re in the business of people, not dollars.