The 5 People Who Will Deep-Six Your Startup's Success Before you start to worry about your startup's demise, remember that plenty of people are on the positive end of the spectrum, too.

As an entrepreneur, you'd like to think that the majority of your success will depend on objective factors: Assuming that your products and services are high quality, you make the right decisions and your timing is right, you'll be successful.

Related: 6 Toxic People Who Are Hurting Your Success

Yet, while these are important factors, they're only a piece of the puzzle. Don't forget that your company is going to be run by, competing with and manipulated by people, and that those people are going to have a massive impact on your company's success, or lack thereof.

On the negative end of that same spectrum describing your business' fate are the following five people with the potential to crush it:

1. The stubborn partner

The term "partner" here can be applied loosely -- this may be a literal partner with whom you share ownership of the business, or an informal partner, such as a cornerstone employee or a mentor. The point is, this person has a vested interest in some important decision but won't budge on his or her opinion. This isn't the same as consistently expressing a different opinion, or even sticking to one's guns on a handful of select issues; instead, this scenario describes a repeated and predictable tendency to be unwilling to entertain alternative options.

And this is bad for two reasons. First, you'll have less of a say in what eventually happens to your business, leaving control in external hands. Second, the fewer discussions you have, the less you'll be able to comprehensively brainstorm.

2. The negative employee

You may think that the level of the employee in question has a significant bearing on the effects of his or her negativity; for example, a star developer and team leader with a negative attitude may be potentially more damaging than a new secretary or assistant. But that isn't always the case.

Negativity, manifested as habitual complaining, pessimism, apathy or a dour personality, is dangerous on one level because it affects productivity and brand loyalty; unhappy, negative workers get less done and are more likely to leave.

But it's dangerous on another, more significant, level because it's infectious. One vocally negative worker can affect your entire team. Fortunately, positivity is similarly infectious if you have the right people carrying a positive attitude.

Related: 5 Types of Toxic Employees and How to Deal With Them

3. The toxic client

In the early stages of your startup's growth, you'll put clients on a pedestal. Yes, clients are important, and you should do everything you can to maximize the number of clients you acquire early on, and keep them happy for as long as possible. But there are cases when a client is doing you more harm than good, and at that point, you need to cut ties before things get any worse.

Toxic clients will never be happy -- they will make strange demands that exceed your capabilities, complain when things aren't perfect, refuse to cooperate and even end up costing you more money than they're spending at your business (not to mention, destroy your team's morale). It's not worth it.

4. The antagonist

The "antagonist" doesn't belong to a particular role (partner, employee, client, etc.) because this personality can manifest itself in multiple contexts. Antagonists are more than simply apathetic about your business, or destructive on their own terms; they take actions that actively hold your business back. Though not always manifested in an act of deliberate or obvious sabotage, recurring actions by an antagonist seem to align themselves against your eventual success.

For example, a worker might refuse to cooperate; a partner might undermine your directives; or a client might ignore your advice and blame you for his/her mistake later.

5. You, yourself

Don't forget that you're the most important person in your startup, and that you're perfectly capable of self-sabotage. You may not realize it, but your fears, apprehensions and biases may actively interfere with your ability to make good decisions or perform your work. To make matters worse, it's harder to spot these traits in yourself than it is in other people; so you may never even know you're doing damage.

Try to stay open and introspective throughout your tenure as an entrepreneur, and always be willing to hear outside feedback.

Before you start to worry about who's going to be responsible for your startup's demise, remember that plenty of people are on the positive end of the spectrum, too. This group will include you, if you allow yourself to be there.

Related: 5 Signs That You Need to Split From Your Partner

There are the supporters, the negotiators, the believers, the hard workers and the loyalists, all of whom are there to help your business succeed. You can't always predict what type of person someone will be in the context of your business, but you do have ultimate control over who's a part of your business and who isn't. Spend extra time up front to make sure the right people become a part of your enterprise, and weed out the toxic members before it's too late.