Several years ago my bank had to store three signatures because I couldn't (and still can't) produce two identical ones. Last year I had to update some documentation and they had to store two more signatures, so now I have 5, but any other signature will be different anyway. The reason is likely that, as a leftie, since being a kid I had to suffer a few attempts to force me writing with the right hand, something I trained by myself much later in my 20s out of curiosity, but quickly forgot due to lack of practice. I never perfected my horrible handwriting and resorted to block capitals immediately after school; then computers and printers solved the problem. Unfortunately it seems there's no way to get rid of this archaic thing called signature that for me translates into wasting lots of time; I'd rather leave a blood sample on paper if I could:)