Are there real world examples of a shoe event horizon?
The dutch disease is when an economy is so dominated by a single export industry that the success of that industry drives up the currency and makes the exports of other industries un-competitive. This drives some of the firms making other goods out of business. 

Continuing this cycle can lead in the short term to even greater concentration of the economy in that industry. 

If later the export industry experiences a significant shock, the broader economy also experiences that shock. This happens for two reasons:


In a diversified economy some firms are experiencing positive shocks when others experience negative ones. In a concentrated economy it is less likely that the other industries will collectively experience an sufficient offsetting shock.
A negative shock to the primary exporting industry is likely to depreciate the currency which should help other industries but shrinking capacity from the expansion will diminish other industries' ability to generate sufficient exports to offset the shock. 


Further, if the industry responds by boosting output (like sometimes happens when oil prices fall and producers become desperate) this can make export prices fall further still, worsening the shock.