Goroutines enable concurrency without guaranteeing parallel speedup

Launching more goroutines can make a program slower when coordination outweighs useful computation.

The Go FAQ explains that concurrency enables parallelism only when the underlying problem permits independent work.

I would partition work around independent operations before increasing the number of concurrently executing tasks.

Communication and synchronization remain real costs, even when the language makes concurrent structure easy to express.

If performance requires measurements, then integration tests should preserve correctness while concurrency changes are evaluated.

Benchmark the actual workload rather than treating goroutine counts as evidence of increased processing capacity.

Choose concurrency to organize overlapping work, and claim speedup only after measuring the resulting execution.