Mary is an at$-$will bank teller at Goliath National Bank. She has worked at the company for $10$ years. Recently, Mary's performance has declined and she is late for work quite a bit. Mary's manager would like to terminate her. However, there is no documentation showing a decline in Mary's performance. Rather, the only documentation is her last employee evaluation in which she received a score of $4$ out of $5.$ If Mary is terminated, your MAIN legal concern is that: