The most likely cause for consistent bad performance is cheap hosting with not enough resources available (processor and memory).

There can be some slowness when the site first starts up and if it is a low traffic site it may be shutting down whenever 20 minutes goes by without a request and this can make it seem slower because it is always having to startup again when you get a visitor. This can be mitigated to some degree by using a free service to monitor your site it will create requests often enough to keep the site warmed up. We have an App Keep Alive Task that can also do this but I think the service would work better.

See Using The App KeepAlive Task to Speed Up a Low Traffic site, it has a link to a free monitoring service.

If that does not help I would consider getting better hosting.

Best,

Joe