In my years of working with struggling companies, I have found most
managers do reasonably well with things they know about.  They can see,
evaluate and formulate a plan of action relative to those things that
is generally effective.  Businesses that are in trouble almost always
got blindsided by something they didn’t see coming.  Often, those
things had been coming on for months or even years, but the manager
either didn’t see (or chose not to see) the signs.  Again, in many
cases, by simply taking time to look around and poke into things, all
that heartache could have been avoided.

i recall one company in particular that waited and waited for an
order from their biggest customer.  After three months (three
months?!?!? you’ve got to be kidding me,) they called the customer,
only to find out he’d decided to switch suppliers.  The business owner
called the big customer to see if he could resurrect the account.  When
he asked why they’d switched, they replied that the service they’d been
getting had not met their expectations.  They were unwilling to return.

I suggested they make a call to their top ten accounts.  Obviously,
if one account (the biggest) had been getting sub-standard service, it
was likely others had as well.  Sure enough, several were about to the
point of leaving.  Now, this business owner / manager was doing well
with the things he knew about.  He hadn’t made any blunders that put
his business at risk.  It was things he didn’t know about (and should
have) that bit him.  Those customer service errors — made by a $5 per
hour employee — cost the company 50% of its revenues and cost 20 people
their jobs (as adjustments were made for the slow-down in business.)

All of that could have easily been avoided had the manager talked to
his customers (at least the top two or three) regularly.  A call once
every month or two to see how things were going would have alerted him
to this huge problem before it got out of hand.  In this case, the
biggest danger to this business came from within (and that’s how it
usually goes.)

If you’re going to know what you don’t know, you can’t sit in your
ivory tower and do nothing.  Your responsibility is to be aware of
what’s going on both inside and outside your company.  You fail to do
that at your peril.  Knowledge is power  –  you can never have enough. 
When you think you know everything that is going on in your business,
you are at risk.  Because at that point you stop looking, so you’re not
going to know what you don’t know.  And after all, it’s what you don’t
know that you should be concerned about.