From a recent engagement
We didn't win the argument. We earned the trust.
One client had a performance problem and almost no way to see it. To diagnose an issue in production, developers added log lines, deployed, connected to servers, read the output, and often removed the logging afterward. We proposed instrumenting the application with OpenTelemetry so traces, logs, and metrics would be available all the time.
The client's senior architect pushed back hard. He reviewed nearly everything that reached production, and he worried the instrumentation would slow down a system that already had performance problems. He'd also watched consultants introduce changes before and then leave him to own the complexity.
Those were reasonable concerns, so we treated them that way. Instead of escalating to leadership, we walked through the implementation with him, compared instrumented and uninstrumented code, showed it didn't materially affect performance, made it easy to switch off, and connected it to the performance problems he was fighting every day.
He stopped seeing us as another consultancy that would leave him a mess and started treating us as a technical partner. That relationship is what made the improvement possible.