When to use the RSpec's let!()

I have been told that it makes sense to use let!() instead of before(:each) block, however I can't see much of a logic doing that. Does it actually make any sense of making something like in the example below

context 'my super context' do
  let!(:something) do
    Model.create(subject: "Hello", body: "World")
  end

  it '...' do
    # We never call something
    # All we want is just evaluate and create
    # the record
  end
end

Keep in mind that you won't call something anywhere in the example at all. Technically I don't see much of the difference with this, unless it's actually more strict and easy to understand without documentation just like plain English

context 'my super context' do
  before(:each) do
    Model.create(subject: "Hello", body: "World")
  end

  it '...' do
    # We never call something
    # All we want is just evaluate and create
    # the record
  end
end

Could someone help me to get the idea behind? Thank you very much!