Here's one scenario in which Rocket Lab stock could be worth $8 a share.Rocket Lab (RKLB 2.81%) stock has taken investors on a wild ride this week, slumping on Tuesday's news that the rocket maker had missed Wall Street's sales target in the first quarter, then recovering on Wednesday.Investors might have felt encouraged that Morgan Stanley analyst Kristine Liwag, in a note on StreetInsider, lowered her price target on Rocket Lab stock to $8 a share. Why would investors think a lowered price target is good ...