In long-term portfolio construction, staying fully invested is often treated as the default, supported by historical return data and opportunity cost arguments. Over long horizons, idle capital tends to reduce nominal returns relative to a fully invested benchmark.
At the same time, some investors intentionally maintain a degree of flexibility through modest allocations to cash or short-duration assets. This can allow rebalancing, deployment during drawdowns, or reduced forced selling during periods of market stress. While this approach may lower expected returns, it may also affect risk-adjusted outcomes depending on how it is structured and used.
From a portfolio construction standpoint, how do you think about this tradeoff? Do you view flexibility as a form of risk management, or as an inefficiency that long-term investors should minimize? How do you approach this in practice over full market cycles.?