# List of hard things * Purifying proteins once you’ve made them is hard and expensive * [[Isotope separation is hard]] * [[Why is it so hard for new materials to make it out of the lab — Outline]] * [[It is hard to explore ideas via texting]] * [[Counterfactuals are hard]] * [[It is hard to interface different simulations]] * [[Trust is hard to scale]] * [[It is hard to capture value from research]] * [[Maintenance is always hard]] * [[Crowdfunding research is hard]] * [[Simulating contact is hard]] * [[Why is telerobotics hard?]] * [[People consistently underrate how hard it is to integrate components into a system]] * (Of course [[Nothing is fundamentally expensive or hard]]) ### Related * [[List of constraints imposed by material properties]]