The Saudis actually wanted to keep a lid on production, my understanding was that the Russians blew the deal up. The only rational thing for the Saudis to do at that point, given they have the lowest cost production and are in a better position to weather it out, is to max output and hurt the rest of the players enough that they come back to the table.
On the plus side we all benefit from lower energy costs which positively benefit almost every sector of our economy except the oil industry. So it's a plus factor in minimizing the impact of the Trump recession. Kind of ironic really that it's responsible in part for driving down the price of stocks in companies that actually benefit from low oil prices.