Complex sentence: Since Wikipedia is a general encyclopedia, it's supposed to summarise essentially all knowledge, and hence accidental or deliberate choice of a limited scope for an article can make notable information disappear from the encyclopedia entirely, or make it highly inaccessible.
Split into simpler sentences: Since Wikipedia is a general encyclopedia, it's supposed to summarise essentially all knowledge. Hence accidental or deliberate choice of a limited scope for an article can make notable information disappear from the encyclopedia entirely, or make it highly inaccessible.