It’s probably one of the most spectacular feat that a scrawl can have. It has such power in the confirmation of an agreement, and you could quite literally sign your life away.

On a personal level, with a scribble, you could get yourself a home (lease/mortgage), a job (contract agreements), the right to travel (visas/passports), somewhere to put your money (bank accounts), change your name and be in a legal partnership with another (marriage/unions). 

Then if you are in high enough position within your workplace, you can pretty much change everything. The image of the organisation, your employees’ salaries, projects’ outcomes. Many can also indirectly affect their communities or over a greater area - just a signature for a building permit, funding to local councils, schools, transport systems, taxes, the kind of information that are made available to the public, etc etc - these can impact of so many tens of thousands of people.

Some biro ink left behind on papers can transform you, others, our surroundings and livelihood in a matter of seconds - that is just extraordinary.