Tesla Inc.
TSLA,
+3.83%
Chief Executive Elon Musk panned the most recent test version of the company's self-driving software, but said that Tesla employees are "rallying to improve (it) as fast as possible." Musk tweeted late Monday that the latest "beta" version of Full Self Driving, released to some select Tesla owners, "is not that great" and is requiring "massive" AI retraining. Stock reaction to the tweet was muted, with Tesla shares flat in the extended session. The stock ended the regular trading day up 3.8%. Tesla last week held an "AI Day," which included the surprise reveal of ahuman-shaped robot that one analyst called “an absolute head scratcher.”