Each fund has a named fund manager, often with a co-manager and a team of analysts behind them. Their job is to pick what to buy, when to buy it, how much, and when to sell, within the rules of the mandate. Their record is public and tracked by everyone in the industry.
Fund managers are employed by the Asset Management Company, which in turn is sponsored by a bank, an insurer or a financial group. The AMC earns a fee for managing the money; it does not earn more by trading more, which keeps its interests roughly aligned with yours.
A change of fund manager is worth noticing, because a fund's long record belongs partly to the person who built it. A new manager with a different style can turn a steady fund into a different fund with the same name.
Know who runs your fund, and notice when that person changes.