This is a drain plug with a very mangled sealing washer. You cannot see it in this picture, but it is very thin, much thinner that it should be, and, as you can see in this picture, a lot bigger then when it was new.

How do drain plug washers grow that much bigger you ask?

Well, for example, if somebody cranks the drain plug tight like they took a double portion of steroids that morning with no regards to the gentle needs of an innocent oil drain plug.

Commonly you would think that changing the oil is something that the aspiring hobby mechanic should have no problem doing.

Not so.

I have seen anything from filling the engine to the top of the filler plug, which would result major drag and no power or non start of the engine, to tightening the drain plug until the lead washer squeezes out on the side, which is the picture you can admire here.

I put a fresh washer next to it to demonstrate just how much this drain plug was tightened. I know, the fear of loosing your oil plug and subsequently the oil over your rear tire with resulting self made oil slick and/or engine damage from oil pressure loss, is grand.

But really people. If the drain washer starts oozing out of the sides of the drain plug like a toothpaste out of the tube, wouldn't you care to think that something is actually WRONG?

The owner of the motorcycle that was accompanied by this squeezy here was lucky, since nothing more happened.

But I have seen it that the engine cases were cracked from asserting too much pressure on the little threads. In which case: you need to take the oil pan off and weld it.

Expensive and a lot of work.

Or: You don't have an oil pan, which older bikes or singles don't typically have, and then you are kinda SOL and either need to live with a leaky pan or do some labor intensive JB weld job every time you change the oil.

So if you are an aspiring mechanic: In your own interest. Do yourself a favor and buy a torque wrench.