- like it feeling so wierd that your left hand is more skilled than it used to be
- to become ambidextrous easing nonsymmetrical future tasks set up in a way that favors the left hand, for example, cutting celery with a knife that was laid on the cutting board with its handle on the left side
- to increase neuroplasticity thus become smarter
It's not known whether or not self-induced left-handedness is more common than self-induced right-handedness. One factor that has a tendency to make self-induced left-handedness more common is that there are more right-handers to become self-induced left-handers. Another factor that has a tendency to make self-induced right-handers more common is that it's inconvenient to be left-handed.
If somebody who was naturally right-handed starts using their left hand all the time for all complex tasks, they will probably become left-handed after enough time goes by; not only that but also their right hand will never have as low a skill level as their left hand would have had if they hadn't made that change, making that change advantageous. Self-induced left-handedness is even more advantageous than self-induced right-handedness because in general, a left handed person has an easier time switching to their right hand than a right-handed person has switching to their left hand so a self-induced left-hander will end up having more skill in their right hand than a self-induced right-hander will have in their left hand. In fact the highest skill a self-induced left-hander would be able to do with either hand only exceeds that of a self-induced right-hander after enough time has gone by for the originally non-dominant hand to exceed the skill level of the other hand but before then, that of a self-induced right-hander exceeds that of a self-induced left-hander. However, the older they are, the longer it will take to become left-handed because the higher the skill they would have already developed in their right hand and so the higher the skill level to catch up to with their left hand. Here are 2 effects that shorten the length of time it takes to become left-handed:
- the slight forgetting of right hand muscle memory
- the slight automatic transfer of skill from one hand to the other. It will be faster for somebody to become good at aiming darts with their left hand if they had already thrown darts with their right hand lots and never with their left hand than if they had never thrown darts before, though it can seem to one to work the other way around for one self due to the frustration of using one's own left hand when they so easily could have aimed very accurately with their right hand.
- transfer of skill from one task to another task (if switching hands for more than one task). A right handed person will be faster at getting good at a specific task with their left hand if they switch to using their left hand for all tasks they would have naturally done with their right hand than if they only switch to doing that task with their left hand and continue to do all other complex tasks with their right hand. There's no big deal in it taking so long to become ambidextrous or left-handed because it takes a much shorter time to become good enough at your left hand to be able to do most complex tasks and just because it's less good than the right hand doesn't necessarily mean it isn't very good.
Self-induced left-handedness in some people would probably be an intermediate evolutionary result of eugenics of ambidexterity. A more common result of eugenics of ambidexterity would probably be an increase in the birth rate of natural left-handers because they get more training with their right hand from adapting to the right-handed world than the other way around but the most common result of eugenics of ambidexterity would probably just be the tendency for difference in skill to divide exponentially exceeding the tendency for it to multiply exponentially.
- In The Princess Bride, 2 sword fighters decide to prove how good a sword fighter they are by using their left hand.
Incomplete self-induced left-handedness
Incomplete self-induced left-handedness occurs when one's own choice to use their left hand when they wouldn't have naturally done didn't make them left handed but only made them less strongly right-handed or ambidextrous. They're still not defined to be self-induced left-handed even if they will be but not enough time of practicing with their left hand has yet gone by for them to become left-handed.