Why were states willing to invest the time and money needed to build canals?

States willing to invest the time and money needed to build canals because it was safer to travel on canals than it was to travel on roads.

Explanation:

There are four transportation system: road, rail, water and air. Each of the transportation system has its own advantage and disadvantages. Water transport is safe to travel as it has less traffic than other transportation system. So, there are less chances of accidents.

Road transportation is comparatively busiest way where excess traffic causes and it is not safe at all like canal. Through canal one can transport lots of goods and cargo to other neighbor states. For e. g. Panama canal, Suez canal are some of the important canal of States used for transportation since ages.