(Via The Business Journals / Spider Graham) — For the better part of the past 25 years, I have been self-employed. I have founded a digital media development company, had a consultancy that focused on the providing strategic services to digital advertisers, and built two companies offering training services.

While working for myself has been rewarding and, at times, profitable, there have also been plenty of challenges and setbacks.

I am reminded almost daily that life is uncertain.

Here are my insights about business success, many of which I learned the hard way:

1. Your mission needs to be driven by passion and purpose, not just money

Certainly money is an important consideration, but going into business simply to create a huge payday is generally a non-starter. The people who end up being successful are the ones that have a dream that won’t leave them alone. These are people whose vision stems from what they can bring to other people. If they’re successful doing that, the income has the tendency to take care of itself.

2. Every business owner and employee works in sales

I speak with people all the time who tell me that they don’t ever want to work in sales. But the simple reality is that anybody who is self-employed or works for a company sells every day. Whether it’s selling prospects on what you bring to the table, talking to potential investors or even just talking to neighbors and friends about what you do for a living, you are a constant representative for the brand — and what you say is heard and remembered by others.

3. You will crash and burn at some point

This may sound negative, but business is filled with uncertainly and a fair amount of disappointment. Sooner or later, every business faces a point where things just don’t come together. Whether it’s clients who flake out and refuse to pay invoices, customers who are unhappy and want money back, or great opportunities that fall through at the last minute, there are plenty of things that will rock you back on your heels from time to time. The good news is that if you accept that it’s going to happen eventually, it’s a lot easier to deal with when it happens.

4. Your competitors are not your enemies

It shouldn’t be a shock that you will run into other companies from time to time who are battling for the same slice of pie that your company is. While you will need to do what you can to win business, you will also find that the people you are up against will understand better than almost anybody in the world just how hard your job is. There have been many times in my career when my competitors have become some of my closest friends. They were the people I could turn to for advice, and even to offer jobs to. Of course you don’t need to share all your trade secrets, but you’ll be surprised at how many cooperative opportunities can be created just by reaching out.

5. You cannot make it alone

The lone practitioner is a tough business model to create success from. The basic reality is that you need help. The greatest architect in the world cannot build a skyscraper alone, and the same holds true for any business. It’s so important to have other people to bounce ideas off of, handle set responsibilities and to share the workload. It’s a lot more fun too.

6. Networking isn’t a nice to have, it’s a need to have

The greatest asset you will have in business are the people you can turn to when you need help, guidance and even money. Isolation in business is deadly. While you may have plenty of work on your plate, setting up lunches, evening gathering and weekend outings with other people who work in your industry can be some of the best time you will ever spend. Schedule at least one event per week to meet with a colleague, professional group or prospect. These are the people who are going to make the biggest difference in your future.

7. Patience is important

Again, not to sound cynical, but it often seems that nothing ever happens at the right time. That contract that you expect to be an easy close turns into a two-month ordeal tied up in a prospect’s legal department. The check that was supposed to arrive on Monday gets sent back to the client because they sent it to the wrong address. The subcontractor who promised you full delivery on Friday calls you on Thursday to tell you that due to a death in the family he won’t be able to make the deadline.

Modern business happens at its own pace. While you may want to control all the outcomes, sometimes taking a deep breath and accepting setbacks is the best thing you can do.

8. Persistence is the key to all success, in business and in life

Perhaps the most important thing I’ve learned in my career is that most success is based on simply not giving up. Things aren’t going to go smoothly or easily most of the time. Expect it and keep pressing on. The people who give up when things get hard rarely accomplish great things. It is only by keeping on keeping on that we eventually accomplish what we want to.

When you get knocked down, get back up and dust yourself off. And if you get knocked down again, just keep getting up. Sooner or later you will get there.