I once heard a man say that everything he sells has nutritional value ~ you buy and he eats!
It is no surprise that the investment product selling industry wants you to believe that today is always a good day to buy. The truth is investment markets do not work that way. There are times when we get to experience a market that is worthy of our investment capital; and, there are times when we experience a market that is not worthy of our investment capital. If you are dealing with anyone who is telling you that today is always a good day to buy, you may want to slide your chair back a bit along with your dinner plate.
So how do you navigate this maze? The best suggestion I have ever heard is to seek out someone with a logical organized approach to investing. It is important that this approach is one that you can understand. It is important that you understand because you cannot maintain personal responsibility if you turn over the investment of your assets and then completely forget them. Your understanding is an accountability issue, not only for your advisor, but for yourself as well. If you do not understand what it is they are doing, how can you discern if they are (and you are) progressing toward your goal?
This is not just about growth of your retirement assets. Growth of your assets is important. However the single, most overlooked aspect of the investment process is wealth preservation ~ avoiding catastrophic losses. If you are about to take 401k investment advice from someone unwilling to clearly explain what it is they are going to do with your assets and how they will navigate bubbles in the market, who has the problem?
It does not matter if your 401k options include a self directed brokerage account or not. You can still benefit from the advice of a professional if they have a high degree of concern for your security and a logical organized approach to investing in all kinds of markets ~ up, down and sideways ~ easily explained and understood. The choice is yours.