People shouldn’t have to read an entire paragraph to discover why you’re writing.
Instead of:
“Due to scheduled system maintenance intended to improve platform performance, users may experience a temporary interruption in service this Saturday between 8:00 and 10:00 p.m.”
Try:
“The platform will be unavailable Saturday from 8:00 to 10:00 p.m. while we perform scheduled maintenance.”
The second version gives readers the information that affects them first. The explanation comes afterward.
Plain language isn’t only about using simpler words. It’s also about presenting information in the order people need it.