Interesting & updated article below from Kim Komando on pros/cons of physically powering off desktops or laptops when not in use. I usually have always done that without major issues. One key advantage is that Windows Updates are often installed during the power off process. Also, when there is a potential for T-Storms everything gets physically unplugged including DSL. Conversely, there are benefits in performing overnight defrags, AV scans, or other maintenance functions. Leaving a system on/off is more a usage consideration than one which saves equipment these days.
QUOTE: For decades, the debate has raged over whether you should leave your computer on every single second or give it regular rest. Both sides believe their way is better for a computer’s life. The shut-it-down crowd believes that leaving it on and working will wear out components faster and shorten your computer’s life. The leave-it-on crew believes that repeated shutdowns and startups will wear out components faster and shorten your computer’s life. In other words, they’re worried about the same thing for completely opposite reasons. So, who is right, and what does it mean for you?