"Inevitable" doesn't mean "unceasing", and "progress" doesn't define an endpoint.

A homeless drug-addicted mugger has an inevitable direction of progress. That progress point is death of some sort. Some of his actions might not lead there, though, in fact, he could turn his entire life around, get help, get clean, get a house, get a good job, SIGNIFICANTLY increase his lifespan, and he will still have an inevitable direction of progress towards death.

No one asks if we're in a downturn in the "inevitable", not a peak but a valley, nor do they ask what we are progressing towards, merely that we ARE progressing to something.