Before the Samsung Galaxy Note5, previous Note models were designed to prevent you from inserting the S Pen the wrong way with the top of the Pen going into its housing first. But with the Galaxy Note5, Samsung created a spring-based method to help users eject the pen out of the phablet. And with this new Technology called "click", Samsung disabled the safety mechanism that prevented the S Pen from being inserted backwards.
On the Note 5, inserting the S Pen the wrong way provides exactly as much resistance as inserting it the right way. Which is to say: basically none at all. Once you insert the pen far enough in the wrong direction (again, which causes no strange resistance or feel than putting it in the right way), it will get stuck. It doesn't even have to "click" in. At this point, of course, you will panic. And you will try to get it out - and most likely, you'll succeed. The problem is that if you do succeed, there's a very real possibility you'll break whatever mechanism the device uses to detect whether the pen is attached or detached from the phone.
If you own the Samsung Galaxy Note5, let this be a warning; you need to make sure that the S Pen is replaced the right way. More importantly, you need to watch those you lend your phone to lest they replace the S Pen incorrectly.
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On the Note 5, inserting the S Pen the wrong way provides exactly as much resistance as inserting it the right way. Which is to say: basically none at all. Once you insert the pen far enough in the wrong direction (again, which causes no strange resistance or feel than putting it in the right way), it will get stuck. It doesn't even have to "click" in. At this point, of course, you will panic. And you will try to get it out - and most likely, you'll succeed. The problem is that if you do succeed, there's a very real possibility you'll break whatever mechanism the device uses to detect whether the pen is attached or detached from the phone.
If you own the Samsung Galaxy Note5, let this be a warning; you need to make sure that the S Pen is replaced the right way. More importantly, you need to watch those you lend your phone to lest they replace the S Pen incorrectly.
SOURCE