Why don’t Russian tank crewman close their vehicle hatches?

SGT (Join to see) good day Brother Charlie, always informational and of the most interesting. Thanks for sharing, have a blessed day!

PO1 William "Chip" Nagel
..."Tank crewmen typical call being enclosed in a tank "Buttoned up" and being halfway out of the hatch "Unbuttoned." Staying Buttoned Up makes you safer, but it becomes harder to navigate and maintain situational awareness."

I thought it was so they could escape when hit by anti tank rounds