bat one thousand
Have a perfect record, as in In meeting deadlines, she's batting one thousand. The term comes from baseball statistics, where it signifies getting a hit for every turn at bat. It was transferred to other activities in the 1920s.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.