University Endowment funds usually restrict Portfolio Managers' direct usage of leverage, derivatives and short selling because:

Short selling, derivatives, and leveraged positions require margin calls.

Regulations on short positions, leverage and derivatives can change frequently

Portfolio Managers may generate very high returns that may impact the fund negatively

Portfolio Managers do not understand how to use leverage, derivatives, and short position effectively

Derivatives, Short selling and Leverage increase the risk of the fund