Keep needing to run manual analyze

We have an application that uses a Postgres database (currently 9.6). All the autovacuum/analyze settings are just left at the defaults.
We've had a few instances recently where users have complained of slow performance and running a manual Analyze (not vacuum) on their database has resolved it.
Should it be considered normal that this needs to be done manually periodically even when autovacuum is on?
It's not a very heavy application by a lot of people's standards (it's just a point-of-sale/stock-control system) but there are a couple of hundred databases on the server, all in fairly constant use through the day.
Is it possible that the autovacuum/analyze isn't running for some reason? If so, is there anything I should look at to make it work better or should I just be looking at scheduling a manual vacuum/analyze periodically on all databases?

I've had a search around but there seem to be lots of differing opinions on what needs to be done manually and what should be handled by the autovacuum.

Any hints most welcome...

Med vänlig hälsning / Best Regards

Rob Northcott
Software Developer (UK Office, formerly TEAM Systems)

Phone +44 1752 712052

Compilator AB
Södergatan 22
SE-211 34 Malmö
Sweden
www.compilator.com<http://www.compilator.com/>

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