That… my friend… would be an unsafe assumption. 
I’ve had both good and bad experiences with filament. If you see some of my earlier posts, I buy on price-only and have posted proof of filaments that have wildly different pricing but obviously come out of the same factory. Among the poorest at quality control has been Bambu of late. I’ve criticize their Silk and Matte PLAs as being very inferior to the competition but at the same time they charge a 60% premium and have bad shipping and return policies.
Since you’re an Amazon customer, hopefully you are also a Prime member. Here’s an open secret I’ve shared here before… Amazon will take back any filament you are not satisfied with even if you’ve used a portion. I would say 10% of my first-time filaments are returned and checked off on my crude spreadsheet as “Blacklisted” while others have been great quality albeit inconsistent pricing. My quest is for the $10 spool which I have hit from time to time but not with any consistency.
This is an example of a dirty plate that was deliberately touched with fingers although the textured build plate “looked” clean.
Here is an example of a smooth plate that shows finger prints more readily. You can see the fingerprints interfere with first layer adhesion.
