That's true. They are also in my deck ;)

I am not knowledgeable enough to know whether or not a business is viable just from looking in the storefront.

Though I would argue that as the owner of two retail locations, I am probably better equipped to make that judgement than most.

In my experience, most retail leases are for 5 year terms. I can't imagine that the default rate on those is anywhere near 50%. Most business "failures" likely never got far enough to sign a lease.

If you're just looking at storefronts, how do you know what's viable and what isn't without making assumptions? Looking at real estate turnover tells you something about the location - and what businesses are appropriate for it - but doesn't tell you much about the viability of any particular business model.