Agreed. The differences of opinion during estimating are another form of pressure. Programmers work differently. I might estimate a task longer than a colleague

Agreed. The differences of opinion during estimating are another form of pressure. Programmers work differently. I might estimate a task longer than a colleague, but I might be the type of programmer who tidies up and refactors along the way, or who spends more time communicating with the team on strategy and architecture. These are hard to quantify behaviors that Jira can't effectively track, unless you're going to spend half your day _in_ Jira writing down every action every day. Don't event get me started on the effect of context switching. Managers are pushed to produce reports to prove they're managing. Reports require metrics, and that's a lot of where all this rubbish starts. The solution in my experience is to keep teams small enough that you don't need those sorts of layers of management (though the opposite is inevitable in larger companies).