Apply suggestions from code review

Co-authored-by: Étienne Barrié <[email protected]>

README.md

@@ -116,8 +116,8 @@ My Title,Hello World!
 
 The Maintenance Tasks gem supports processing Active Records in batches. This
 can reduce the number of calls your Task makes to the database. Use
-`ActiveRecord::Batches#in_batches` to specify that your Task should process
-records in batches. Active Record defaults to 1000 records, but a custom size can be
+`ActiveRecord::Batches#in_batches` on the relation returned by your collection to specify that your Task should process
+batches instead of records. Active Record defaults to 1000 records by batch, but a custom size can be
 specified.
 
 ```ruby
@@ -149,7 +149,7 @@ operation such as `#update_all` or `#delete_all`. If you need to iterate over
 individual records, you should define a collection that [returns an
 `ActiveRecord::Relation`](#creating-a-task). This uses batching
 internally, but loads the records with one SQL query. Conversely, batch
-collections load the primary keys first, and then perform a query to load the
+collections load the primary keys of the records of the batch first, and then perform an additional query to load the
 records when calling `each` (or any `Enumerable` method) inside `#process`.
 
 ### Throttling