Leaving signals, speaking explains
Customers who quietly walk away only tell an organization that something is wrong. Complaints also tell it why. Speaking up therefore carries far more usable information for repairing a decline.
Business

Customers who quietly walk away only tell an organization that something is wrong. Complaints also tell it why. Speaking up therefore carries far more usable information for repairing a decline.
The easier it is to leave, the less likely people are to bother protesting. Leaving and speaking up work like a seesaw. Where switching is cheap, the people who might have demanded improvement simply go.
Choosing to complain means giving up a certain escape for an uncertain chance that things will improve. How willing people are to make that trade decides whether they use their voice or simply leave.
People who have no alternative to switch to are often assumed to be ignored, since they cannot leave. The book argues the reverse. Having no exit makes them push harder from within, so their voices grow louder.
If loyal members stay but have no effective way to be heard, their loyalty no longer drives repair. It becomes quiet acceptance of decline. Without working channels for complaint, loyalty can lock the deterioration in place.
Staying put despite dissatisfaction often comes from sunk costs that make switching feel more expensive than it is. It also comes from ideology or emotional ties to group identity. These attachments override present unhappiness with hope that things will improve later.
When a firm, group, or state gets worse, its members can respond in two ways. They can leave and take their custom elsewhere, or they can stay and push for change from within. Leaving is the market's way of reacting; speaking up is politics.
When a rival is available, the most quality-conscious members are the first to leave. They are exactly the people whose complaints would have forced a fix. For goods prized by connoisseurs, a tight monopoly can therefore beat weak competition, because it keeps the demanding customers inside and complaining.
Attachment to an organization holds members in place after a rival would have lured them away. That buys time for their complaints to work. Loyal members commit hardest when they believe they will be heard and can actually reform the place.
Exit and voice substitute for each other, so shutting down one channel loads pressure onto the other. An organization that stifles complaint pushes unhappy members toward leaving, its only remaining outlet. Making room for criticism can keep them from going.