Lincoln Cents have been zinc planchets plated in copper since 1982 and this process took a while to perfect. In the meantime the plating didn’t often completely adhere to the zinc planchet and the air in these areas would expand and create bubbles of all shapes and sizes. You can actually poke and burst these shapes and bubbles.
Once these pockets are breached it doesn’t take long for the zinc oxide to form and eventually zinc “rot to occur. These plating pockets don’t add any value to the coin. Plating bubbles in and shape don’t add any value to a coin, but I have seen collectors pay a premium for them because the coin was misrepresented as something else or the collector thought it was something it is not. However, an extreme example of plating bubbling might go for a few dollars on occasion.