The left hemisphere of the brain that is often associated with neurocognitive functions as well as logic, knowledge, calculation, etc. processes information sequentially, processing one data at a time as in linear and logical manner. The left hemisphere is the one paying attention to technicalities such as errors in spelling, calculation, etc. that is why the left hemisphere needs to process information one at a time.
The right hemisphere, on the other hand, is often associated with creativity, art, and emotions processes information globally, reflecting on information as a whole as thoughts that are processed by the right brain are not intricate but are whole some and should not be objectified sequentially.