But maybe not. Sometimes trouble sneaks up on a supposedly strong brand and knocks it right off course, but at other times the signs of breakdown have been there for some time. Unfortunately, those in charge ignore the signs, blithely believing success is theirs by right.
This is particularly scandalous in retailing, since, more than almost any other sector, it should be in tune with shifts in changes in customer perception and/or demand. When it isn't, the damage can be severe and long-lasting.
Which is why John Lewis, despite being such a venerable institution of retailing, should be looking a bit more closely at what's happening inside its real world stores which are, after all, its core business. Because it's not a pretty sight. Just as with Marks & Spencer a few years ago, the negative word of mouth about customers' experiences is becoming much more commonplace.
Here are just two, admittedly anecdotal but still indicative, instances of why the retailer's profits have been headed in a downward direction for the past few years.
A customer goes into one of the main London branches to buy a top of the line washing machine, armed with information gathered about brand and price. The white goods department is full of ignored and increasingly disgruntled-looking customers who would actually like to buy something.
The few hapless sales people just can't cope or are really not all that interested.
What they don't seem to realise is that every fed-up customer who walks away means less in the pot for the annual division of profits among the 40,000 'partners'.
Next instance. A couple goes to the carpet department in another big branch. They are keen to re-carpet their whole house, but need lots of advice about what's best to buy. They go to John Lewis because the retailer has in the past always been a brand they trust unreservedly for getting things right or, at the very least, fixing them fast if something goes wrong. Again, there are many customers milling around looking for help, but the sales people available appear to have far more important things to do than serve customers.
Negative word of mouth is relentless. It might not affect your bottom line today or even tomorrow, but ultimately you pay the price unless you take some fast remedial action.
What's particularly ironic in the case of John Lewis is that it has been exemplary in the enlightened way it treats its staff, long before the concept of empowerment became part of management jargon.
It's just that somewhere down the line those at the top stopped reminding the employees about the link between the money that pays for those perks and where it comes from. It's what Colin Shaw and John Ivens, in their new book Building Great Customer Experiences, call an inside-out culture.
Being inside out means that the needs of the firm are put before the customer experience, with processes developed to make life easier for employees. The effect on customers is resentment, exasperation and irritability.
With inevitable results. The employees should probably enjoy those holiday homes and yachts while they can.