My advice would be to develop a system that allows you to carefully ensure you never cross-contaminate chemistry. You can use one graduate with rinses between each step, or separately identified/marked/coloured multiple graduates - just make sure your system includes appropriate spacial or temporal safeguards.

Then use your system each time, without fail.

Some chemistry is very susceptible of contamination - a s bath developer like Diafine comes to mind - so it deserves its own specialized version of your system.

FWIW, I do not dedicate graduates to particular chemicals. I depend on temporal and spacial safeguards (including thorough rinsing) to protect me.

It is worth noting, however, that if you are going to share your darkroom with others, dedicated graduates are a very good idea.