NOT SO GOOD REALLY BAD

Sometimes, things start well but then get worse. They can...

... get into a mess or be in a mess: The company accounts are in a complete mess. It will take weeks to sort them out.

... go wrong (= stop working well): If things start going wrong in your life, you should talk to someone about it.

... go pear-shaped (UK ifml.) (= stop being successful):

Manchester City started the season well, but it all went pear-shaped after they lost two home matches in a row.

Sometimes, things start badly and then get even worse. They can... ... get off to a bad start:

Our neighbours complained about us as soon as we moved in, so things got off to a very bad start.

... go from bad to worse:

Then their children broke our window, so things went from bad to worse.

If something is nothing to write home ⋅ about, it’s not special in any way:

The Hotel Excelsior is OK, but it’s nothing to write home about.

If something is nothing special, it’s similar to other things you’ve seen or places you’ve been to:

Milan is quite a nice city, but it’s nothing special.

In conversation, people in the UK often say things are rub bish:

What was the lecture like? – It was absolute rubbish. No one understood a word he was saying. You can say something is a (complete) waste of time:

The meeting was a complete waste of time. We didn’t discuss any of the important issues.

If an idea or a plan is a non-starter, it’s so bad that it’s not even worth starting on:

Their plan for the motorway is a non-starter. It would go straight

through a nature reserve.