We want to make sure phrases begin correctly and consistently.
Correct beginning case makes the meaning clearer to end users.
Clearer meaning makes it easier to make a good translation.
Consistent beginning case makes it easier for developers to work with.
Consistent beginning case is a sign of higher quality product.
Incorrect beginning case could be a sign that partial phrases are in use or an error has been made.
Problem should be self explanatory.
If it is legit you could address this by adding a [comment] or [asis] to the beginning for clarity and to make it harder to use as a partial phrase.
[comment,lc because …]lowercase this must be for some reason. [asis,brian d foy] is really cool!