Biological systems are so complex that reproducing results is extremely hard even if the authors publish their method in detail, simply because they might not know why it works for them.

This is hard to understand for software people, since code tends to behave reproducible as a default.

Basically the only way to reproduce a difficult finding is to learn the procedure at the original lab.

An example: A friend of mine could not reproduce his own findings in another lab. Turned out the precise type of the lamp build into the setup mattered.

Another example: I could not reproduce a finding the was something I wanted to build upon. Turned out the precise method to dissolve one of the chemicals in the buffer as the problem. It was even hinted in the paper, but who would describe in detail what he means by “ vigorously stirred” ?