... tax back for your research

What if my research was unsuccessful?

There is no requirement that your research be successful.

From the CRA's Information Circular IC 86-4R3:

"The search for a meaningful advance in the body of scientific or technological knowledge should be present as a guiding element in every eligible project. This requirement is satisfied whether or not the activity is successful. In other words, determining that a hypothesis is incorrect also represents a scientific or technological advance."

It can also be easier to prove that "scientific or technological uncertainty" was involved when a project was unsuccessful, since it is unlikely that a company would pursue a development that it already knows is infeasible.