It isn’t because of fabricated results, but rather that some of these analyses are very difficult to perform. Some papers require specific techniques or tools t

It isn’t because of fabricated results, but rather that some of these analyses are very difficult to perform. Some papers require specific techniques or tools that aren’t widely available. Some depend on biological samples that were exhausted. Some used poor experimental design. There are lots of reasons why a particular paper might be difficult to replicate. Academic publishing tends to reward those that make big discoveries or find something novel. Unfortunately, reproducibility isn’t as high on the priority list as it should be. But all that said - the amount of outright fabricated data is pretty small. Many people can make mistakes or overstate the meaning of their data. But the amount of people who flat out fake their data is really small. And institutions are more likely to loose grant money if they turn a blind eye than if they self regulate.