I may be misunderstanding how to use the milestone, sorry in advance if I am.

I have a simple pipeline configured as follows:

node('some-node') {
    stage('First') {
        milestone 1
        input(id: 'input', message: 'Deploy?')
    }
    stage('Second') {
        milestone 2
    }
    
}

If I have builds 1 and 2 sitting at the input step, and I "reject" build #2 so that it does not proceed any further, build #1 is still automatically aborted. This does not make sense to me, because build #2 has not reached "milestone 2". Please advise.