Laravel multiple select array validation always give error

If your select looks like this for example:

<div class="form-group row">
    <label for="skills" class="col-md-4 col-form-label text-md-right">Skills</label>
    <div class="col-md-6">
        <select multiple name="skills[]" id="skills" class="form-control{{ $errors->has('skills') ? ' is-invalid' : '' }}" required>
            <option value="ios">iOS</option>
            <option value="php">PHP</option>
            <option value="laravel">Laravel</option>
        </select>
        @if($errors->has('skills'))
            <span class="invalid-feedback" role="alert">
                <strong>{{ $errors->first('skills') }}</strong>
            </span>
        @endif
    </div>
</div>

Create a custom request:

$ php artisan make:request ExampleRequest

ExampleRequest validation would look like this:

public function authorize()
{
    return true;
}

public function rules()
{
    return [
        'skills' => 'required|array',
    ];
}

Then just grab the validated data from your $request directly

public function submitForm(ExampleRequest $request)
{
    // at this point, validation already passed
    // if validation failed, you would be back at form with errors
    $skills = request('skills');
    // or
    $skills = $request->skills;

    dd($skills);
}

Custom requests are being validated first before even hitting your controller method.