The Astros ordinarily are a good fielding team. However, in the last month and a half the Astros have made an uncharacteristic number of errors and misplays. In order to clinch the AL West down the stretch and attempt to progress through the playoffs, the Astros must clean up these errors and misplays.
According to Fangraphs, the Astros playoff odds currently stand at 97%. So it would take a total collapse not to make the playoffs. But if there is a way to make such an unlikely collapse occur, a contagion of errors and misplays would probably do it.