docs: add why

Author: jasonraimondi

README.md

@@ -6,7 +6,7 @@
 [![GitHub package.json version](https://img.shields.io/github/package-json/v/jasonraimondi/nestjs-axios-promise?style=flat-square)](https://github.com/jasonraimondi/nestjs-axios-promise/releases/latest)
 [![NPM Downloads](https://img.shields.io/npm/dt/nestjs-axios-promise?label=npm%20downloads&style=flat-square)](https://www.npmjs.com/package/nestjs-axios-promise)
 
-A thin wrapper around [Axios](https://github.com/axios/axios) for [Nest.js](https://github.com/nestjs/nest) using Promises, because the [@nestjs/axios](https://github.com/nestjs/axios) package returns an observable.
+A thin wrapper around [Axios](https://github.com/axios/axios) for [Nest.js](https://github.com/nestjs/nest) using Promises, because the [@nestjs/axios](https://github.com/nestjs/axios) package returns an observable. See [#why](#why)
 
 ## Install
 
@@ -53,3 +53,53 @@ export class MyCustomService {
 })
 export class AppModule {}
 ```
+
+### Why
+
+Because I find our way using a promise
+
+```ts
+import { AxiosService } from "nestjs-axios-promise";
+
+@Injectable()
+export class CatsService {
+  private readonly logger = new Logger(CatsService.name);
+
+  constructor(private readonly httpService: AxiosService) {}
+
+  findAll(): Promise<Cat[]> {
+    const { data } = await this.httpService
+      .get<Cat[]>("http://localhost:3000/cats")
+      .catch((error: AxiosError) => {
+        this.logger.error(error.response.data);
+        throw "An error happened!";
+      });
+    return data;
+  }
+}
+```
+
+MUCH more preferrable to the nestjs way of using an observable. They're casting their observable to a promise anyways... :facepalm:
+
+```ts
+import { catchError, firstValueFrom } from "rxjs";
+import { HttpService } from "@nestjs/axios";
+
+@Injectable()
+export class CatsService {
+  private readonly logger = new Logger(CatsService.name);
+  constructor(private readonly httpService: HttpService) {}
+
+  findAll(): Promise<Cat[]> {
+    const { data } = await firstValueFrom(
+      this.httpService.get<Cat[]>("http://localhost:3000/cats").pipe(
+        catchError((error: AxiosError) => {
+          this.logger.error(error.response.data);
+          throw "An error happened!";
+        }),
+      ),
+    );
+    return data;
+  }
+}
+```