Why do my tests sporadically fail/pass?

I'm writing some pretty basic tests to assert that a project has been created and that an event is fired.

This first test will fail 50% of the time, and pass 50% of the time:

    /** @test */
    public function an_authenticated_user_can_create_a_project()
    {
        $name = 'This is the project name';
        $project = Project::factory()->make(['name' => $name])->toArray();

        // Logged out
        $response = $this->post(route('projects.store'), $project);
        $response->assertRedirect('/login');
        $this->assertDatabaseMissing('projects', $project);

        // Logged in
        $this->signIn($user = User::factory()->create());
        $project = Project::factory()->make([
            'name' => $name,
            'creator_id' => $user->id
        ])->toArray();
        $response = $this->post(route('projects.store'), $project);
        $this->assertDatabaseHas('projects', ['name' => $name]);
    }

The failure message is:

  • Tests\Feature\App\Http\Controllers\ProjectTest > an authenticated user can create a project
  Failed asserting that a row in the table [projects] matches the attributes {
      "name": "This is the project name"
  }.
  
  The table is empty..

I'm using the RefreshDatabase trait in the tests.

The second that fails 50% of the time is:

/** @test */
public function a_project_created_event_is_dispatched_on_project_created()
{
    $this->signIn();
    Event::fake();
    $this->post(route('projects.store'), Project::factory()->make()->toArray());
    Event::assertDispatched(ProjectCreated::class);
}

Failure:

  • Tests\Feature\App\Http\Controllers\ProjectTest > a project created event is dispatched on project created
  The expected [App\Events\ProjectCreated] event was not dispatched.
  Failed asserting that false is true.

Here is the basic controller method I'm testing:

public function store(CreateProjectRequest $request)
{
    $project = Project::create([
        ...$request->validated(),
        'creator_id' => auth()->id()
    ]);

    ProjectCreated::dispatch($project);

    return Redirect::back();
}

Any help welcome, I just don't understand why sometimes they pass and sometimes they fail?!