Why did Hungary join the Austro-Hungarian Empire led by Austria, which was completely different from itself in history?

It was not Hungary that wanted to join, but the Austrian emperor wanted to consolidate his influence on Hungary, so he negotiated with Hungary's optimates, and the Hungarian nobles proposed to establish a dual regime, which actually strengthened the Hungarian nobles' right to speak in the empire. However, the establishment of the empire only took care of the interests of Hungarians, and other ethnic groups had almost no rights, which aggravated ethnic contradictions and social unrest.