A hung parliament means ineffective government because politicians from different parties don’t want to work together.
There are coalition governments working effectively all over Europe, as well as in the Scottish Parliament and Welsh Assembly. There’s no reason to think they wouldn’t work well here too. By the way, no other country uses the term ‘Hung Parliament’ which in itself is a major scare story. ‘Coalition Government’ is the term we should use.
In order to avoid the type of system we have today, where the majority in power can pretty much do anything they want, a coalition government would require negotiation and deeper thinking before passing laws. It would hold all the politicians to account for their votes, thereby ensuring that decisions are made to benefit the country, not the individual politicians or the parties.
On the contrary, a coalition government may slow the legislative process somewhat, but the eventual result, as tempered by multiple viewpoints, is far more representative of what the public want. The result will be more effective, not less so.