The only reason to invest is if you think the market will, eventually, go up. That’s been the trend, so that’s the thinking.

No one is any good at figuring out when it will go up or down in the short term. If this is the low point, of course you should buy! If it’s going to drop further, you should wait! But nobody knows.

Because the market on average tends to go up; at any given time investing now on average means you’ll capture more of that growth, and waiting means on average you’ll miss out out growth. Not always, like you saw over the last year, but usually.

The biggest mistake with a lot of investing is being too nervous. Missing the gains and only investing afterwards is also a way to at least lose in opportunity cost.