This article originally appeared February 7, 2018 on ETF.com here.

Those who fail to plan, plan to fail. And while most people would never start a business without a business plan, many investors manage their money without an investment plan that identifies their ability, willingness and need to take risk, sets goals (such as the rate of return they require their portfolio to generate) and that includes an asset allocation and rebalancing table to provide discipline.

Compounding the problem of a failure to plan is that even a well-thought-out investment plan is only a necessary condition for success, not a sufficient one. Even the “perfect” investment plan can fail for reasons that have nothing to do with its investment results.

Examples of how plans can fail for noninvestment reasons include the premature death of a family’s main income earner combined with insufficient life insurance, forced early retirement, the lack of sufficient personal liability insurance (such as an umbrella policy), poor estate planning (such as neglecting to keep beneficiary designations updated), the lack of appropriate medical insurance (such as long-term care coverage) and even living longer than expected.

This is why the right approach is to create a fully integrated estate, tax and risk-management plan.

These issues have always existed. However, today’s investors, whether they’re planning for retirement or already in the withdrawal phase, face four hurdles that their predecessors didn’t. If these hurdles aren’t planned for, the odds of ending up without sufficient assets to maintain a desired – let alone a minimally acceptable – standard of living can greatly increase.

In biblical tradition, the four horsemen of the apocalypse are a quartet of immensely powerful entities personifying the four prime concepts – war, famine, pestilence and death – that drive the apocalypse.

For today’s investors, the equivalent of those four horsemen are historically high equity valuations, historically low bond yields, increasing longevity and, as a result, the increasing need for what can be very expensive long-term care.