I am so sick of all these theories. IT'S SIMPLE...
Char builds up on the wick over time and is impossible to clean off entirely. You may be able to get some off with all these methods people come up with but the bottom line is you'll never get it back to new. Disect an atty and you will see for yourself. Remover the bridge and look at the wick running through the coil. It looks like charcoal. Scrape away at it with a pin and you'll see what I am talking about. Atty's are disposable.
Char builds up on the wick over time and is impossible to clean off entirely. You may be able to get some off with all these methods people come up with but the bottom line is you'll never get it back to new. Disect an atty and you will see for yourself. Remover the bridge and look at the wick running through the coil. It looks like charcoal. Scrape away at it with a pin and you'll see what I am talking about. Atty's are disposable.