Having worked on other hardware consoles, I suppose that we were rather spoilt by having mature toolchains that integrated nicely with our development environment. Wii U on the other hand seemed to be trying at every turn to make it difficult to compile and run any code. Nintendo had provided an integration of their development tools into Visual Studio - the de facto standard for development - but it didn't work, not even close. So time was spent trying to get this fixed up, while reporting the issue to the platform holder. Eventually we received a solution from Nintendo via another third-party company who had also been working on this issue for a while.
So now we could make the code visible in Visual Studio and get it compiling, which was good, but the compilation times were really slow, even for minor changes. Then it had to do the link step, at which point you could happily get up, make a cup of tea, have a chat and get back to your desk before the link was complete. Link times were measured in multiple (four or more) minutes on Wii U compared to around one minute on other platforms.
This doesn't sound bad, but when you are debugging and making lots of changes, these additional times add up. If you made 10 changes to a file in a morning, you could be spending over 50 minutes waiting for the linker to complete, which is a lot of wasted time.