"verifying" signatures is an inherently insecure practice anyway. It's trivial to copy a signature any many people (like me) have poor writing that varies each time anyway. It's more about showing intent than verification.
If you signed something and cannot make it look reasonably like what I understand your signature to look like, I have a really big red flag telling me you aren't who you say you are. Then I then have the option of denying you, or investigating why you can't match your own signature, and looking at other available proof of your ID.
People's signatures may change a little over time, but there are clear muscle-memory related aspects that don't disappear. It's the most basic aspect of handwriting their is - your own name. Usually it's the first thing you even learn how to write. If you can't do that, then you definitely need to carry plenty of other forms of ID that don't need your signature. And even your driver's license has that. Outside of physical or mental damage, there is very little excuse in the world for not being able to duplicate your own signature satisfactorily.
If you signed something and cannot make it look reasonably like what I understand your signature to look like, I have a really big red flag telling me you aren't who you say you are. Then I then have the option of denying you, or investigating why you can't match your own signature, and looking at other available proof of your ID.
People's signatures may change a little over time, but there are clear muscle-memory related aspects that don't disappear. It's the most basic aspect of handwriting their is - your own name. Usually it's the first thing you even learn how to write. If you can't do that, then you definitely need to carry plenty of other forms of ID that don't need your signature. And even your driver's license has that. Outside of physical or mental damage, there is very little excuse in the world for not being able to duplicate your own signature satisfactorily.