“Whoever loves his life loses it, and whoever hates his life in this world will keep it for eternal life” (John 12:25).
I don’t think he means that we are supposed to engage in self-sabatoge to make our life harder than it has to be.
For example, I heard of a charity in the developing world once that refused to have a hot water heat put in, even though donors had fully provided for it, because they believed that there was extra virtue in having to put up with just having cold water.
That’s not the meaning of hate your life!
Instead, I think what Jesus means is that following his commands is hard. Which means that, at one point or another, there is going to be a cost to it.
As a result, sometimes when we follow his commands, life will go “less well” for us in this world. It will look like we hate our lives. Because we do in the sense that Jesus intends here — we love them less than him. And so whenever there is a conflict between what he commands and what will go better for us, we follow his commands. And we do this, if necessary, even to the pointing of losing our lives in martyrdom (Revelation 12:11).
Now, let’s apply this to productivity. “Hating your life” does not mean you don’t seek to grow your business as much as you can, or that you don’t seek to advance in your career. Rather, it means that you do so in line with Jesus’ commands. That will often involve sacrifice. But you don’t sacrifice for its own sake.
To go back to the example of the charity. If there was another charity nearby that needed a hot water heater, and only one was available, it certainly would be right and good for them to say “give it to them — we will continue to do without.” That’s Christian love (Philippians 2:4ff).
But to refuse the increased productivity and better tool out of some principle that advancing and having better tools is not healthy and good — that is not what Jesus is talking about.
For more on this, see John Piper’s devotional “How to Hate Your Life.”