Gabe and Frankie decide to have a contest for ownership of the winery with the winner being the one who brings in the most grapes. The reality is that in quality winemaking a low yield is preferable - the energy of the vines are spread through fewer grape clusters. You also want smaller berry size so that the ratio of pulp to skin surface is as low as possible. And you want to use very little water. Overwatering creates plump, tasteless grapes with lower sugar and acid.
When Frankie and Nate rush to turn on each sprinkler in the vineyard when the new water pump is malfunctioning, each sprinkler turns on by turning a knob. If the pump did not work, opening each valve would not have worked. The valves would have had to be open if they were to have functioned with an operating pump.