Jira has always had performance issues. Now a lot of groups do a great job of making things worse.
If your company is hosting their own, they usually don't spec the servers well enough for the load.
Next, lots of companies will add customizations and scripts behind the scenes which will absolutely cripple Jira as well.
As others said, most of these tools are pretty annoying. Jira can be pretty good when it's set up well.
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