When developing the processes and policies that govern when and how your organization's users interact with procurement, it's easy to get bogged down in the minutiae of it all, make them overly broad, or, worse, just copy what someone else does. Your procurement policies and processes should be determined, not by what's industry-best, but by what's best for your particular needs and organizational workflows.
Want an example of why this is bad? Here.
A recent report on Vox.com brings up the problem of utilizing someone else's best practice. Amtrak, in its major metropolitan stations in Boston, D.C., New York, and Philadelphia, uses a boarding system for their trains much like the U.S. airports use for boarding airplanes. Passengers stand in line and show tickets to the guard before gaining entrance to the boarding platform.
In theory, this is understandable. Ticket queues are used by airports, who see 815M passengers a year. Amtrak, by comparison, only moves 31.2M passengers a year. By copying the airline method, Amtrak is using the most-tested, most-proven boarding process they know. Except its specifically tailored to the airline industry.
Planes have a single point of entry, and specialized equipment is needed to physically get people from the waiting area onto the plane. Trains have multiple doors, and require no special equipment. A single-file boarding process, while sounding great in theory, is ineffective (and possibly insane) for a railroad company. By copying the most tested, most proven boarding method, Amtrak is ignoring those factors that make them unique, and not exploiting the methods that could improve boarding speed i.e. using those multiple doors.
Taking it back to procurement - companies are very quick to instill boilerplate procurement policies and implement rigid policies, without factoring in their own unique situations and needs. Using a stodgy, n-step procurement process, full of meetings with and confirmations from multiple parties and rigid limits, just because it's what market leader X implemented, will very likely not be the most efficient choice for your own organization.
That's not to say that someone else's procurement policies aren't great for other uses. Use them as building blocks. Break them down; analyze every step, task, clause, and subtask; and figure out what can be streamlined, modified, or cut out entirely. At the same time, further tailor in your policies by adding in your own requirements - potentially on a team and departmental level - based on what each team's and department's needs are. Review requirements are probably slim for office supplies - a Bic is a Bic - but Production might need a longer, more stringent review due to the complexity and variety of the products ordered and the high tolerances required.
In short, implementing a procedure just because a market leader did is probably not the best way to go about things. Your unique needs should trump "market best".