I have been working on reproducing computational biology papers from the cancer field lately. I am very frustrated. When the inputs and outputs are machine-readable data, there's no excuse for not making your work reproducible, in my opinion. Often the problem is plain laziness and disorganization.
One major problem is that there's not much real incentive to make your work reproducible. Money granting organizations favor researchers breaking new and exciting ground, not those rehashing an already published method. Publishers don't require reproducible methods, and reviewers don't have the time, desire, nor expertise to do an in-depth methods review.
Wet lab experiments are 1-2 orders of magnitude more expensive and difficult to reproduce, that's true, but we're not even getting the basics right!
One major problem is that there's not much real incentive to make your work reproducible. Money granting organizations favor researchers breaking new and exciting ground, not those rehashing an already published method. Publishers don't require reproducible methods, and reviewers don't have the time, desire, nor expertise to do an in-depth methods review.
Wet lab experiments are 1-2 orders of magnitude more expensive and difficult to reproduce, that's true, but we're not even getting the basics right!