docs: clearer policy > metadata schema & reqs (#275)

## What Did You Change?

Clearer language in the "Metadata Schema and Requirements" section.

## Do You Want Support (syntax, design, etc)?

Someone else two review the new wording. I privately requested @mesteva
review.

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## Any Reference Material Worth Sharing?

[internal collab
doc](https://docs.google.com/document/d/1a1KSeyezPCwjDIHBSP2EEwauWFUKy_RiVVqKVepUAUA/#heading=h.fs1mjdamsvw3)
(see suggestions in green)

Author: wesleyboar

user-guide/curating/policies.md

@@ -251,9 +251,9 @@ The expectations of DDR and the responsibilities of users with respect to licens
 
 ## Metadata Schema and Requirements { #metadatareqs }
 
-For each project type, the metadata elements including those that are required (\*), recommended (&), and generated by the repository system (!) are shown below.
+For each project type, the metadata elements shown below are marked as required (\*), recommended (&), or generated by the repository system (!).
 
-Many fields are only recommended because users may not have information to fill them. For example, researchers may not have been awarded a grant to conduct research toward a dataset and therefore no information to input. We strongly encourage filling as much recommended metadata as possible so if you have been supported by a grant, please fill that information. Once you click and start filling a recommended field, corresponding sub-fields become required.
+Many fields are only recommended because users may not always have the information needed to complete them. (For example, researchers may not have been awarded a grant to conduct research toward a dataset and therefore not have information to input.) We strongly encourage users to complete as many recommended fields as possible. Note that once you begin filling a recommended field, its corresponding sub-fields become required.
 
 Consult the full metadata [Dictionaries](/user-guide/dictionary/) for more details.