Polish "Clarify usage of BufferingApplicationStartup"

See gh-25075

Author: snicoll

spring-boot-project/spring-boot-actuator-autoconfigure/src/docs/asciidoc/endpoints/startup.adoc

@@ -4,24 +4,23 @@
 The `startup` endpoint provides information about the application's startup sequence.
 
 
-
 [[startup-retrieving]]
 == Retrieving the Application Startup steps
 
-To retrieve the steps recorded so far during the application startup phase , make a `POST` request to `/actuator/startup`, as shown in the following curl-based example:
+To drain and return the steps recorded so far during the application startup phase, make a `POST` request to `/actuator/startup`, as shown in the following curl-based example:
 
 include::{snippets}/startup/curl-request.adoc[]
 
 The resulting response is similar to the following:
 
 include::{snippets}/startup/http-response.adoc[]
 
-
+NOTE: Each such call removes the returned steps from the buffer.
 
 [[startup-retrieving-response-structure]]
 === Response Structure
 
-The response contains details of the application startup steps recorded so far by the application.
+The response contains details of the application startup steps.
 The following table describes the structure of the response:
 
 [cols="2,1,3"]

spring-boot-project/spring-boot-docs/src/docs/asciidoc/production-ready-features.adoc

@@ -122,9 +122,8 @@ The following technology-agnostic endpoints are available:
   Disabled by default.
 
 | `startup`
-| Shows the startup steps data collected by the `ApplicationStartup`.
+| Shows the <<spring-boot-features.adoc#boot-features-application-startup-tracking,startup steps data>> collected by the `ApplicationStartup`.
   Requires the `SpringApplication` to be configured with a `BufferingApplicationStartup`.
-  More details about the implementations can be found at <<boot-features.adoc#boot-features-application-startup-tracking, application startup tracking>> page.
 
 | `threaddump`
 | Performs a thread dump.

spring-boot-project/spring-boot-docs/src/docs/asciidoc/spring-boot-features.adoc

@@ -485,8 +485,7 @@ Once configured, you can record data by running the application with the Flight
 
 Spring Boot ships with the `BufferingApplicationStartup` variant; this implementation is meant for buffering the startup steps and draining them into an external metrics system.
 Applications can ask for the bean of type `BufferingApplicationStartup` in any component.
-Additionally, Spring Boot Actuator will <<production-ready-features.adoc#production-ready-endpoints, expose a `startup` endpoint to expose this information as a JSON document>>.
-Be aware, that during startup endpoint processing, all the collected steps will be pulled from the buffer, and sent in the response - so the further requests won't get the startup steps again.
+Additionally, Spring Boot Actuator will {spring-boot-actuator-restapi-docs}/#startup[expose a `startup` endpoint to expose this information as a JSON document].
 
 [[boot-features-external-config]]
 == Externalized Configuration