Many job descriptions are actually a listing of the problems that happened with the last employee.
"Efficient in MySQL" = the current SQL queries are not performing well.
"great code writing style" = the existing code is unreadable
"Understanding of HTML" = they spent more time fixing divs and attributes than writing new code
"Strong database architecture and implementation skills" = we can't afford to hire a DBA as well
"Team Leader" = there are existing employees who we don't trust in a management role
"Ability to work independently" = that last person was always asking questions that could have been Googled
There's sometimes a huge mismatch between what the employer is asking, and his needs.
For example, at my current job we're asking for an expert in HTML5, JQuery, CSS2.1, CSS3, JavaScript, Ajax, Mobile Web Development, Mobile Web Performance, Cross-Browser, Cross-Platform Development; debugging tools (Firebug or equivalent), DOM, Internationalization, Localization, Apache.
The truth is, we have one of the ugliest websites, on an awful CMS, and our webpages are on ASP (not .NET, plain old ASP circa 1999) with VBScript hosted on IIS 5.
What such a rockstar web developer will be doing here beats me (the company does pay way above average wages locally, but such a developer can work for the US).
We've already wasted somebody who was a decent web programmer (he's doing mailing lists for the Marketing department), I guess that the selected applicant will end up doing ASP pages (maybe they'll let him migrate portions of the website very slowly).
In return, I ask that an employer provide some substantive description of what I'll be doing, giving me the opportunity to think about it.
Actual job posting I saw recently:
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Requirements:
* Object Oriented PHP
* Efficient in MySQL
* Experience with programming logic, great code writing style
* Understanding of HTML
* Strong database architecture and implementation skills
* Team Leader
* Ability to work independently
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This tells me pretty much nothing.