docs: Add Motivation (#3)

* Add Motivation

* ci: Format code

* Fix sentence

* Fix typo

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Co-authored-by: Seam Bot <[email protected]>

Author: razor-x

README.md

@@ -9,13 +9,41 @@ Serializes JavaScript objects to URLSearchParams.
 
 Defines the standard for how the Seam SDKs and other Seam API consumers
 should serialize objects to [URLSearchParams] in HTTP GET requests.
-
 Serves as a reference implementation for Seam SDKs in other languages.
 
 See this test for the [serialization behavior](./test/serialization.test.ts).
 
 [URLSearchParams]: https://developer.mozilla.org/en-US/docs/Web/API/URLSearchParams
 
+## Motivation
+
+URL search parameters are strings, however the Seam API will parse parameters as complex types.
+The Seam SDK must accept the complex types as input and serialize these
+to search parameters in a way supported by the Seam API.
+
+There is no single standard for this serialization.
+This module establishes the serialization standard adopted by the Seam API.
+
+### Why not use [URLSearchParams](https://developer.mozilla.org/en-US/docs/Web/API/URLSearchParams)?
+
+Passing a raw object to URLSearchParams has unpredictable serialization behavior.
+
+### Why not [qs](https://github.com/ljharb/qs)?
+
+- Not a zero-dependency module. Has quite a few dependency layers.
+- Impractile as a reference implementation.
+  Since qs enables complex, non-standard parsing and serialization,
+  this makes ensuing SDK parity much harder.
+  Similarly, this puts an unreasonable burden on User's of the HTTP API or those implementing their own client.
+- The Seam API must ensure it handles a well defined set of non-string query parameters consistency.
+  Using qs would allow the SDK to send unsupported or incorrectly serialized parameter types to the API
+  resulting in unexpected behavior.
+
+### Why not use the default [Axios](https://axios-http.com/) serializer?
+
+Using the default [Axios] serializer was the original approach,
+however it had similar issues to using URLSearchParams and qs as noted above.
+
 ## Installation
 
 Add this as a dependency to your project using [npm] with