Why bitbucket ends up in GREEN though recent command exits with a non-zero code?

I've a simple Dockerfile that just pushes the newly built .apk file to the Google Play Console with help of Fastlane tool.

Dockerfile

FROM ruby:3.0-slim-buster

WORKDIR /app

# Copy android project contents. It has an .apk file at ./android/app/build/outputs/apk/release/app-release.apk
COPY ./android .
RUN rm Gemfile.lock

# Install Fastlane
RUN apt-get update
RUN apt-get install build-essential -y
RUN gem install bundler
RUN bundle install

# Upload the apk file
ENTRYPOINT bundle exec fastlane upload

docker-compose.yml

version: '3'

services:
  push-android:
    build:
      dockerfile: ./android/Dockerfile
      context: .
    deploy:
      resources:
        reservations:
          memory: 2048M
    networks:
      - internal

networks:
  internal:
    driver: bridge

My bitbucket-pipelines.yml step goes like this:

- step:
    name: Push APK File
    caches:
      - docker
      - node
    services:
      - docker
    size: 2x
    script:
      - docker-compose up push-android

When I run the above step, it pushes .apk file successfully to the Google Play console. All good with the code so far and with Bitbucket pipeline as well.

But if I re-run the pipeline, it is expected to fail(the Bitbucket pipeline should end up in RED, because we already uploaded an .apk with the same versionCode already in previous build pipeline). As expected, command bundle exec fastlane upload fails with non-zero exit code. But pipeline still ends up in GREEN. But I expect to see it in RED.

Sharing captured image to see the problem visually.

I've even tried by simplifying the Dockerfile to debug the issue by reducing the blast radius or suspicious area.

Updated Dockerfile

FROM ruby:3.0-slim-buster

# There is NO such shell script with this name. So, it should fail with some non-zero exit code.
ENTRYPOINT ./push-apk.sh

Sharing captured image to see the problem visually.

May also this information is useful to you to understand the situation better.
If any command while building the image fails, I see bitbucket pipeline ends up in RED as expected.
Ex, Dockerfile

FROM ruby:3.0-slim-buster

# There is NO such shell script with this name. So, it should fail with some non-zero exit code.
RUN ./push-apk.sh

Bitbucket pipeline ends up in RED when I run above Dockerfile changes.

Explained above, all the different situations that I encountered/tried to debug the issue. Hope it's all helpful.
According to bitbucket docs, build will fail(or go RED) if exit code is non-zero.
As part of debugging process, I've even tried after-script from Bitbucket to log the $BITBUCKET_EXIT_CODE. It logged 0 exit code, that's why we see GREEN. But I don't know how to debug further, that why my shell command exit code is not passed to pipeline? or why $BITBUCKET_EXIT_CODE is 0 .

Could someone tell me where I'm going wrong by considering the above situations? Why my bitbucket pipeline doesn't go RED when the recent executed command fail with a non-zero exit code?

Because docker-compose up push-android itself does not fail if a service exits with a non-zero code.

You probably want docker-compose run push-android instead in this context. This will propagate the exit code.