although this does look Taylor made for for POET, challenges can be made by unsuccessful bidders, and may very well result in delays in completion of the process.

In my experience, most of these occur during the technical evaluation part of the process, where bids are determind to be technically compliant, or not.  After this, its usually a fairly straightforward process where low priced technically compliant bid wins.

Going back to the technical evaluation, a bidder may claim though their product or offering doesn't quite meet a particular requirement or is somehow different than what is being described, it still meets the overall goal or performance requirement for a successful product as intended in the specification.  One must not confuse the terms performance requirement with design requirement as specifying the latter may not allow for new, novel or different solutions to be considered, therefore is usually avoided.

The burden of proof of an alternative but equivalent means to meet the same specification lies with the bidder.  They can't just claim its equivalent, they have to prove it clearly and concisely, and all of this proof must be included in the original bid package.  If there is insufficient information in the bid for a determination of compliancy (or equivalency), it is deemed non-compliant.  There is no recourse here, as the bidder can't provide new or missing information as part of a challenge.

To minimize potential challenges from technically non-compliant bidders, it is critical the technical authorities drafting the specification are extremely clear and unambiguous in their specification or statement of work.  Of course, if there are challenges, they must be prepared to defend their decision in clear defensible language based on their technical expertise and (only) the information presented to them in the bid.

full disclosure, the above based on typical north american practices....