Samsung’s Galaxy Note 5 comes with a number of features and one big design flaw. If an owner of the device reinserts the S-Pen stylus back into it the wrong way, it can permanently disable its stylus detection features.
That’s in part because the design of the Galaxy Note 5’s S-Pen allows the S-Pen to be easily inserted in the wrong direction. If the stylus is inserted incorrectly, it can get caught in the spring mechanism that holds the pen in, as Ars Technica found. They were able to get the S-Pen out after wiggling, but it also disabled the S-Pen detection features in the process.
That means a number of the Galaxy Note 5’s built-in tools that kick in when the stylus ejects will fail to work, including the circular S-Pen menu and the ability to jot down notes while the screen is off. They were able to get it working again after re-inserting the stylus backwards -- a method that doesn’t sound like the greatest idea if you just managed to get the S-Pen unstuck.
The same problem was demonstrated in a video released by Android Police. In their case they were able to replicate the flaw, but were unable to get the stylus out after inserting in the wrong direction. This wasn’t possible on the Galaxy Note 4, since the S-Pen that came with it had a larger tail end to prevent this from happening.