On Yom Kippur, Jews pray their way through several different catalogs of sins, asking for forgiveness for long lists of human failings. The mistakes I’m talking about here don’t necessarily have any spiritual significance, they simply have the capacity to stall or even shut down a business.

The following are ones I have personally seen in action; perhaps knowing about them can help you avoid their calamitous consequences. 1. Going after the trappings rather than the essence of business. In my one very mistaken attempt at a business partnership, a big source of friction was my partner’s delight in meetings that, to me, accomplished little or nothing. She equally couldn’t understand why I took no pleasure in sitting around a conference table going down an agenda of to-do’s that we’d already discussed. «Haven’t you always wanted to have a business?» she retorted once when I objected. We spent too much time on unproductive tasks. I’ve seen others devote so much fuss to their logo, office decor, computer setup or long-range strategy that they don’t have energy left over to deal with finding and keeping clients. Concentrate on core business tasks. 2. Relying too much on one client. You’re asking for trouble if more than 40% of your business comes from one source. Yes, it’s tempting to enjoy the easy pickings of a client who wants to use you more and more and more. However, I’ve had several clients show up at my door having to rebuild their businesses after their too-big client retrenched, refocused or decided it no longer suited them to use you. Foster your economic security by serving a variety of clients who couldn’t all go bust at once. 3. Not keeping an eye on the long term. For about a year and a half during the Internet boom, I had a lucrative contract with a dot-com company that tried to hire me full-time, offering to match whatever I was making on my own. I refused, because it would have meant ditching the momentum I’d built up on the Internet and elsewhere. I saw business owners give in to the siren call of «money now» and either as employee or entrepreneur place all their bets on a new venture that imploded within two years. Having sold off or let go of their previous successes, they had to start again from scratch. Forgoing some quick opportunities now for sustainability in the long run was a smart move, I believe. 4. Sticking with low-profit «sure things» for too long. When some activity reliably brings in business, it’s difficult to let it go, even when it takes much too much effort for its financial return. From 1988 to 2001, one-shot adult education seminars in Cambridge, Boston, Providence and elsewhere were a vital feeder for me, bringing me clients who needed help with their writing projects.

But each seminar meant driving through rush hour traffic, parking, getting home late, making less than $10 an hour when considering the total time spent, all to acquire clients who paid me much less than those who needed marketing help. I should have quit doing these seminars several years before I finally did and invested the energy elsewhere. At least once a year, think about what you’re doing, and drop activities that are not worth the time or hassle. 5. Ignoring collections. A friend who’d worked as a bookkeeper told me about a client of hers who had rarely sent out bills because it was boring to do so, compared with the everyday social dealings he enjoyed in his business.

No wonder he had a problem with cash flow! Judging from the number of very late bills I receive from solo business owners, this must be a common habit.

Understand that you’re not simply delaying payment when you neglect to bill in a timely manner and when you don’t aggressively and quickly go after non-payers. You’re actually jeopardizing your income, because the longer the time goes before someone is asked to pay for a service or product they received, the less likely you are to get that money at all. According to the American Collectors Association, once four months have gone by, you’re only about 80 percent likely to get paid. After six months, only 67 percent of collections ever get cleared. Send those bills out on time! 6. Getting discouraged. One of the most helpful books I’ve ever read is “Mastery” by George Leonard, a pioneer in the human potential movement and a teacher of aikido, a martial art. He explains the normal learning curve for any kind of human endeavor, whether learning a language, a musical instrument, a physical skill or the process of building a business. The normal learning curve includes a stage called «plateau,» where progress seems to cease and there may even be some backsliding, even though the effort put in stays the same. Yet the plateau stage is often followed by a sudden spurt forward, as long as the person keeps at it. Keeping at it in the absence of visible results does not sound like an important success skill, but often that’s the ingredient that separates those who make it from the quitters who give up right before their efforts are about to pay off.