Generally speaking, this is because Airtable doesn’t like commas, at least not in the primary field. :slightly_smiling_face:
Airtable inherently sees commas as a separator between record names, so if it sees one in a primary field, it wraps any field value which references it in quotes to prevent it from being read as two separate records.
Say you have a linked record field. If you were to take a value like “ABC, DEF” and paste it into that linked record field, it would create two records on the linked table: “ABC”, and “DEF”.
It is good practice to avoid commas in the primary field; though depending on your use case, it might not matter at all.
Hope this helps!