The number of defunct ETFs hit 1,000 this year and should be considered “healthy and natural in a thriving—albeit brutal—market.” This according to a recent Bloomberg article.

“On the practical side,” the article explains, “the victims are often thinly traded products that tend to have wider spreads.” More broadly, however the ETF market has evolved into a meritocracy– in contrast to mutual funds, “many of which have props to help them grow assets: distribution fees, spots in 401(k) plans and, most important, a big base of assets that grows with the market.”

Without such aids, the article notes, ETFs must accumulate assets “the hard way: appealing to cost-obsessed, after-tax, picky advisers and do-it-yourself investors. It’s a tough place to live, but it’s where most of the new investor cash is going. That means new launches will remain abundant despite the rising death toll.”

Shutting down ETFs once carried a stigma, the article reports, until industry leader BlackRock Inc. began routine closures about seven years ago. “This opened up the floodgates, increasing both the number of closures and the average size of the closure, which jumped from $15 million to $30 million pretty much overnight.”

While investors harbor no risk of losing their investments in the event of an ETF closure, liquidation could trigger a taxable event, the article reports.  The average lifespan of a dead ETF, it concludes, is “a mere 3.4 years—slightly less than an NFL running back’s career.” Investor patience is key, “but it can be too much to bear in many cases. And sometimes it’s just best to say goodbye.”