The shelf produces a new essential ingredient every few months. Retinal, then PDRN, then NAD+, then peptides, then EGF, each arriving with the confidence of a settled question.
The reasonable worry is that you are falling behind. The arithmetic suggests something else.
The arithmetic nobody does
Start from what testing one product actually takes. One face, one new variable, and long enough for a trend to separate from a good week.
Stella holds an observation window of six to eight weeks before a read lands on a single product. Shorter than that and you are reading weather rather than climate.
A year holds about six of those windows. Six honest answers, assuming nothing overlaps and nothing goes wrong.
The cycle is not outrunning your attention. It is outrunning your calendar.
Why the slots cannot be shared
The constraint that makes it six rather than twenty is that the variables cannot overlap.
If three products start in the same fortnight, no outcome can be attributed to any of them. You will have spent the money and still not know which one to keep.
This reads as pedantry until you have done it twice and been unable to answer a simple question about your own bathroom shelf.
What gets researched instead
Faced with more candidates than slots, attention drifts to whichever question can be closed tonight. Sourcing is usually the one.
Where an ingredient comes from — plant, synthetic, byproduct — is genuinely researchable in an evening. Whether it does anything on your face is not.
