That's like saying I lost money because I didn't place a bet on the winning horse in the Kentucky Derby.
The fact is that just about everyone who remained in the market doing dollar-cost averaging suffered REAL losses in their portfolios.
I didn't make up the term, it's standard economics. Of course, economists are about as trustworthy as Trial Liars and weathermen.
But the gist of what you say is true: if you sit out, you might not lose, but you surely won't 'win' in the market.
If the stock market were measured in some objective way, for instance "The Immodium Factor", maybe we'd all feel better.
In any case, it beats Nazi Social Security every time.