The standard for progress in shale development has been the drastic reduction in the number of days needed to drill a well, from more than 20 to less than 5 in some unconventional plays. But some question whether it has become a misleading metric for an industry needing more productive wells. “The human tendency is to optimize within a given constraint. Right now, it is reaching the total depth in the shortest time,” said Robello Samuel, technology fellow, drilling, at Halliburton. “If all you care about is that quantification, you do not worry about tool damage or wellbore quality, or what it is like to complete it.” Maximizing drilling performance and efficiency is not the same as optimizing it, he said. “Everyone needs to remember why they are drilling the hole. As much oil and gas needs to come out as possible,” said Bart Critser, geosteering manager for Terra Guidance. “Otherwise it’s just a multimillion dollar, fancy hole in the ground.” The payoff for drilling faster has largely been realized. While further time savings are possible, the discounts now offered by service companies hungry for work have slashed the potential savings. In September, the day rate for a typical rig in the Permian Basin was USD 18,000, according to Hart Energy Market Intelligence. That is equivalent to only 360 bbl of oil at USD 50/bbl. Saving a day of drilling is a bad trade if the hole quality suffers. The downsides of a badly drilled well can range from casing damage and pump breakdowns, to missed sweet spots and accumulations of sand in low spots slowing the flow, according to drilling experts at the recent SPE Annual Technical Conference and Exhibition (ATCE) held in Houston, and in interviews since. One of them, Moray Laing, oil and gas lead for the SAS Americas Energy Practice, raised a seemingly simple question: “Having good directional control gives you better wellbore quality. I wonder why we are not measuring that systematically?” The Search for Measures of Drilling Imperfection