You’re making some bizarre assumptions. Not everything is front end user facing.
Let’s say I’m processing messages off a queue. P90 @ 50ms vs p90 at 100ms doesn’t necessarily make a difference. What are my downstream dependencies? What difference does it make to them?
At the end of the day, value is what you care about - not necessarily chasing a metric because lower is absolutely better. What’s the cost of another x milliseconds of latency considering other trade offs (on going operational burden, extensibility, simplicity, scalability, ease of support etc etc).
If 50 ms latency means I can have a solution that can auto scale to massive spikes in traffic due to seasonality or time of day vs a reduction of that latency but I have to spend time capacity planning hardware and potentially holding extra capacity “just in case”, then again, optimizing for a single metric is pointless.
Let’s say I’m processing messages off a queue. P90 @ 50ms vs p90 at 100ms doesn’t necessarily make a difference. What are my downstream dependencies? What difference does it make to them?
At the end of the day, value is what you care about - not necessarily chasing a metric because lower is absolutely better. What’s the cost of another x milliseconds of latency considering other trade offs (on going operational burden, extensibility, simplicity, scalability, ease of support etc etc).
If 50 ms latency means I can have a solution that can auto scale to massive spikes in traffic due to seasonality or time of day vs a reduction of that latency but I have to spend time capacity planning hardware and potentially holding extra capacity “just in case”, then again, optimizing for a single metric is pointless.