because i got three of my LCD broken almost at the same time.
I've been using an LCD monitor for the past 4 years. Apart from a few minor problems (which were easy to repair) there have been no other issues. Sometimes you'll have to replace the backlight when the monitor goes dim. It's cheaper to just replace the backlight instead of replacing the whole monitor. You also need to check the quality of electrical supply in your house to make sure your monitor doesn't go bust. LCD monitors last anywhere from 6-10 years (or more) if maintained in a proper environment.
The LCD panel itself lasts for many years. It is the backlight or its inverter power circuit that tends to fail earlier than the panel. These could be the problems of your LCD monitor. If they failed almost at the same time, your AC power mains might be experiencing spikes or surges. Your PC might next be affected unless connected through UPS/AVR.