Complex sentence: The desirable turnover, also the positive turnover or functional turnover, means low employee performance is replaced by the higher employee performance which brings fresh ideas and perspectives to the company; and dysfunctional tumover is the reverse, causing the remaining employees to pick up the slack.
Split into simpler sentences: The desirable turnover, also the positive turnover or functional turnover, means low employee performance is replaced by the higher employee performance. Higher employee performance brings fresh ideas and perspectives to the company, while dysfunctional turnover is the reverse, causing the remaining employees to pick up the slack.