Why does Netanyahu need to dismiss the key service boss?

dpa
The boss of Israel’s home secret service is to be launched – as a result of there isn’t any longer any belief. The step might increase to a constitutional disaster.
https://www.faz.net/aktuell/politik/ausland/ronen-bar-warum-will-netanjahu-den-geheimdienst-chef-entlassen-110362111.html