Does this indicate a problem?

[JT46]

This image (link below) shows a serial number that has been partly scratched out and then re-engraved by hand (apparently). I see this a lot on Tudors on E-bay. Everything else about the watch looks good and the seller photographs these findings very clearly, indicating the seller doesn't perceive a problem. But it still sends up warnings signals to me. (I think to myself; 'was this stolen at one point?', etc.)

Is this common? Does this indicate a problem or is the scratched and re-engraved serial number due to some other cause? Why isn't the model number similarly affected?

Thanks for your thoughts and experience.

(No implications or disrespect at all intended to the seller of this watch; I am just using this image as an example of a commonly represented finding on E-bay watches.)

http://img.auctiva.com/imgdata/1/3/9...49558271_o.jpg