How were the Dutch able to overtake the Spanish and Portuguese in dominating global trade?

Explanation:

The Dutch–Portuguese War was an armed conflict involving Dutch forces, in the form of the ... Prior to the union of the Portuguese and Spanish Crowns, Portuguese ... Like the French and English, the Dutch worked to create a global trade ... the monopoly of trade with Japan. while the Dutch were unable in four attempts to ...

i think it would be reparing roads  

nothing certain is known about what happened, but it seems that the country declined gradually, perhaps due to bad government, or, more likely, due to a series of bad harvests, which resulted in widespread and recurrent famine.