(DOCS-11076): Document inaccuracies when inserting documents (#2149) (#2186)

* add information about insert inaccuracies

* copy review feedback

* tech review feedback

Author: davidhou17

source/includes/fact-insert-inaccuracies.rst

@@ -0,0 +1,8 @@
+Even if you encounter a server error during an insert, some documents 
+may have been inserted. 
+
+After a successful insert, the system returns |writeResult|, the number 
+of documents inserted into the collection. If the insert 
+operation is interrupted by a replica set state change,
+the system may continue inserting documents. As a result,
+|writeResult| may report fewer documents than actually inserted.

source/reference/command/insert.txt

@@ -151,6 +151,14 @@ Write Concerns and Transactions
 
 .. |operation| replace:: :dbcommand:`insert`
 
+Insert Inaccuracies
+~~~~~~~~~~~~~~~~~~~
+
+.. include:: /includes/fact-insert-inaccuracies.rst
+
+.. |writeResult| replace:: :data:`insert.n`
+
+
 Examples
 --------
 

source/reference/method/Bulk.insert.txt

@@ -39,9 +39,15 @@ Description
         - Document to insert. The size of the document must be less than or
           equal to the :limit:`maximum BSON document size <BSON Document Size>`.
 
-          
-   
+Behavior
+--------
+
+Insert Inaccuracies
+~~~~~~~~~~~~~~~~~~~
+
+.. include:: /includes/fact-insert-inaccuracies.rst
 
+.. |writeResult| replace:: :data:`BulkWriteResult.nInserted`
 
 Example
 -------