1. Starting before you know what the website should look like
Do you remember that cartoon that resurfaces every few years? There is a dozen computer programmers behind their terminals in a room. The development manager is walking out the door while looking back to address the team "OK, you all start programming. I'll go upstairs to find out what they want the program to do".
For anyone who has worked on a computer, the paradox is obvious: How can they produce anything of value if they don't know what the business needs?
It is the same with a website. If you don't know exactly what you want, you will likely waste your effort.
For companies that can afford it, a designer is usually hired to draw up what the website is to look like. They can simply be a "business artist" who delivers images of proposed screenshots based on what the company's goals, brand, message, color scheme and so on are.
For companies who can't afford such a designer, scouring the Internet for websites that you like can work. Out there somewhere, someone has already designed a website that might be perfect for your business. Use that website as a design guide for your website development team.
2. Opting for a Fixed Price Instead of a Budget
Many companies deliver website projects to their clients on a "fixed bid" basis. That is, they offer to build the website for, let's say $20,000, before they even know what the website is supposed to do. In almost every case, this turns into a significant overrun of costs, and all the unhappiness that results for it.
If you (the website owner) don't know exactly what you want yet, and you hope to use the project to flush out requirements as you go, set aside a budget of dollars that will be "eaten through" as you refine what you want, and as the development team (often an outside company) works towards a completed website. As you get near to exhausting the budget, consider adding more money in stages as you go. This model applies the cost to the parties that control it, and supports the business principle that "you pay for what you control".
3. Taking Too Long to Go Live
Websites that sit on a server hidden from the world are useless. If you are a small company, or if you don't have any traffic on your existing website anyway, consider going live within a few weeks of the project and developing the website in a live environment. Travelers on the Internet have a high tolerance for seemingly "unfinished" websites, so don't worry about raising a few eyebrows. It is how the new world of blog , bulletin boards and spontaneous social media sites works today. Visitors to your website are the best source of feedback you can get, so let them see what you are working on as early as possible. In addition, material goes stale. If you wait a few months for everything to be "ideal", the earlier stuff you added to the website will need refreshing again. Get comfortable with the odd spelling mistake or missing punctuation mark, and Go Live Early!
4. Ignoring the Website After Going Live
Going Live is the beginning of the website project, not the end. After you Go Live early, get ready to add fresh content to it every business day of the year. Search engines favor daily active websites over inactive ones by an order of magnitude. So if you want to ever appear at the top of search results when strangers go looking for the kind of product or service you offer, be prepared to add content to your website every day!
5. Leaving Page Titles Blank or Without Keywords
A web page's title is one of the Top Three most important factors for making your website attractive to search engines. Imagine a resume that had the title "Welcome to my resume" on the top of it! Many companies make a similar mistake on their websites by having "Welcome to my website" on every page title! Search engines have a harder time working out what is on the page, when the title doesn't help. Make sure every page on your website has a unique title, each containing likely keywords relating to the page's content. Consider each page title to be a kind of "search engine lottery ticket number". Better to have lots of them, each with a different number.
6. Talking about Your Company instead of your Customer
People browsing the Internet looking for a solution are more interested in themselves that they are interested in you. Use your home page to talk about the kind of problems you solve. For example: instead of "Acme Plastics has been in business since 1922, serving consumers all over the world.", use "Are you looking for rain and freeze resistent plastic grommets for you boat? That's what we make!"
7. Using a HTML Editor, instead of a (Web) Content Management System
Many businesses still develop their website using a desktop tool like FrontPage or Dreamweaver, and push it up to the web server when they are ready. While that is fine for the odd few pages you wish to publish and never change again, any business today that is serious about developing its web presence today uses a Web Content Management System like WordPress, Drupla, Joomla, and so on. These programs sit on the server close to the website and allow the website developers and content contributors to advance the webste by interacting with it using a browser. Long story short, it is the only way you ever want to grow a website today.
8. Not Having the Business Owner Involved at Every Step
Ten or fifteen years ago, it was OK to have a website developer sitting in the basement working on the corporation's website. Websites didn't matter so much in those days. Today, however, an organization's website is often at the core of their strategic Web presence. No one knows a business better than the person who owns it and runs it every day, so if you run your own company, get involved with the development of the website and stay involved at every stage.
9. Leaving the Website Development Project up to the Webmaster
Along the same lines as point 8, above, it is tempting to leave the entire website project up to the people who have the technical knowledge to pull it off. Even a bright, educated and motivated software developer will need to know what the purpose of the website is in order to make a success of it. Bring the development team closer to the core business decision makers. In addition, consider dropping the term "Webmaster". If there is any such thing, the owner of the company, even if he or she is the CEO of General Motors, should be considered the Webmaster. Technical staff working on your website are not "masters" of anything except -- hopefully -- the technical tools they use to deliver value to their client of employer.
10. Not Being Clear About the Purpose of the Website
The primary purpose of a website for a small company is to Generate Leads. Is your website generating leads? Do you have a means on your website to capture the contact information of the visitors who arrive there? Consider adding a connection from your website to a Contact Management System like ConstantContact.com or iContact.com to help you capture such visitors' information. These external systems have gotten very advanced, and are capable of managing your marketing conversation with huge numbers of prospects and customers and driving your business forward. If you just want the contact information to be handlied manually, take a look at emailmeform.com or contactmeform.com. These easy to use tools allow you to add a wide range of contact info collection forms to your website.
As always, Good Luck out there.