The same reason that people visit the gym on a regular basis, is probably the same reason you’re interested in raising your IQ. We just aren’t challenged enough physically or mentally. Setting aside time to work your mind out and organizing your various mental muscles can help you to be more creative, solve problems quicker and focus on the things you want.
Contrary to what most people believe, brainpower goes beyond inherited genes. Scientists have proven that intelligence is a combination of both genes and environment. When laboratory rats were given more toys to interact with, they ended up having much smarter rats than the ones that did not have any toys. Studies have also shown that you can grow more neurons with a stimulating environment.