Here is reproducible codes:

context 'when narrowed down results' do

  before do
    3.times do
      Person.create
    end
  end

  it do
    expect(Person.gt(age: 0).order_by(name: 1).to_a.count).to eq 3

    Person.gt(age: 0).order_by(name: 1).first

    expect(Person.gt(age: 0).order_by(name: 1).to_a.count).to eq 3
  end

end

2nd Person.gt(age: 0).order_by(name: 1).to_a.count is expected 3, but its actual is 1.