Contract Web Designers Often Set Their Hours
For the most part, contract (and some permanent) Web developers can set their own hours. If you are a self-motivated person, this is great. If you tend to turn on the computer to play Solitaire before you start your day, this can be deadly (If you find yourself thinking "I know I'll win the next game," you should think hard about this).
Web Pages are Always On
The tricky part with developing Web pages comes with the nature of the Web - it is international, and your customers can be too. Even if your customers are not international, they may want to have their Web page geared towards a different time zone than the one you're in. At Netcom, all press releases were supposed to go up at 5:30am EST. When I worked there, I lived in California, 3 hours behind EST. We often wouldn't receive press releases until 9pm Pacific time, and the PR people would want them up at 5:30am East Coast time. That meant that if I could get the release formated in HTML in 10 minutes (working at home in my pajamas of course), I could go to bed around 9:30pm and get four and a half hours of sleep.
And Web pages never seem to go down during the day. If you're a Webmaster responsible for the server maintenance, you often have to carry a pager and you will get paged -- at two in the morning. And a Web site is a serious thing to most businesses. It is not a pleasant thing to know that the only reason the Vice President knows your name is because the site was off-line for four hours the other day.
Web Developers are Called at All Hours
What it comes down to is that Web pages go down in the middle of the night, and your customers will then call you to fix them, in the middle of the night. As a Web developer, you have to be ready to service your customers whenever they need you to.
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