"Thanks for trying Kickstart," reads the now-static landing page for Yahoo!'s (NASDAQ:YHOO) employment-hunting social network. "Please check out Yahoo! HotJobs for your job-search needs."

How's that for a "don't call us, we'll call you" sendoff?

Kickstart is -- make that was -- a more recent effort by Yahoo! to cash in on elusive social-networking success. It seemed like a bold initiative when first proposed two summers ago. Just as Facebook was expanding its reach beyond the college crowd, Kickstart was supposed to swoop in as a more serious connection tool for college kids more interested in firing off resumes than polishing off beer kegs.

In a perfect world, Kickstart would have made HotJobs a hipper place to recruit college grads than the blander job boards offered by Monster (NASDAQ:MWW) and Dice Holdings (NYSE:DHX). But in the end, Kickstart just never quite lived up to its self-starter moniker.

Yahoo! also recently shuttered Mash, the company's more conventional social-networking site, before it even had a full year under its belt. It's a miracle that Yahoo! 360 is still around. 

Doesn't Yahoo! get it? When Yahoo! President Sue Decker called Yahoo! Mail a "dormant social network" last year, with 250 million accounts at the time, Yahoo! seemed to have the necessary tools to create the mother of all social-networking sites. Why is it shutting sites down without giving them a real chance, mocking the time and effort put in by loyal users? At this rate, if and when Yahoo! puts out a real social-networking site, it'll be hard for wary potential users to take it seriously.

Social stickiness doesn't happen overnight. Even the typically smart Google (NASDAQ:GOOG) is closing down its Lively avatar-driven virtual environment. Google's single social networking hit is Bebo, but that was an acquisition, not an in-house development.

Yahoo! is in cost-cutting mode so it needs to prioritize, but the success of Facebook and News Corp.'s (NASDAQ:NWS) MySpace should prove that Yahoo! must make social networking a priority.

Otherwise, on some not-too-distant day, the Yahoo! landing page may thank users for trying the site, and direct them to Google or Live.com for their search needs.

Yahoo!'s social miscues: