What's the difference between what appears as Load and what doesn't appear in the log when accessing DB?

For example, if you run all, the character User Load appears.

User.all
 User Load (3.5ms) SELECT "users".* FROM "users"

On the other hand, when you run pluck, SQL itself seems to be the same, but User Load is not displayed.

User.pluck(:name)
(1.9ms) SELECT "users". "name" FROM "users"

At first, I thought it was the difference between loading it into memory, but
I think loading pluck into memory is the same, so I wondered what the difference was.

 names=User.pluck(:name)
(1.9ms) SELECT "users". "name" FROM "users"

names 
=>["foo", "bar" ]

If anyone knows the difference between XXX Load and as shown above, could you please let me know?