supply demand question beginner I am learning about shifts in supply and demand. Things that shift supply include things like improvement in production technologies. But why would a firm want to increase their supply if they are just going to sell more product for less at the new equilibrium ?
The new "equilibrium" would have been at a lower price on the assumption that the firm has full Monopoly over the market (and hence cannot instead just compete with some other firm for a larger share of market demand) and demand remains constant. 

Moreover unless you know about the elasticity of demand (how sensitive people's wish to buy is with regards to commodity price) you cannot be certain if selling a significantly larger amount at a slightly smaller price might in totality fetch the producer a larger sum of money.