Product Performance Improves or Declines After the First Few Uses Or Bottles?

   I have noticed sometimes that the first time I apply or first few times I use a skincare product it wows me and then with repeated usage it doesn't seem to have the same magical touch. On the flip side some skincare products my skin really doesn't like at first but since I paid good money for it I don't want it to go to waste and then it seems to work better after a week or two.

    For example, I recently got the Lush Ayesha Mask and the first time I used it, it blew my socks off - no stinging or irritation but when I washed it off my skin was soft and smooth like I had done a painful chemical peel. The following times I used it I got good results with soft smooth skin but nothing like the first time I used it. Another example was my first bottle of the Ordinary Buffet, the first bottle I went through I saw results in short time my skin was much smoother, lines softened incredibly and oddly even my pores looked smaller. I used that bottle up and reordered and I'm on my second bottle and although I'm getting good results from it the pore reducing magic seemed limited to the first bottle, which I thought I was rather odd as I think the quality of the first and second bottle is the same.

  An example of products working better after multiple uses was when I used Trilogy's Age Proof CoQ-10 Booster Oil. I was thick and greasy at first for the first week or two of daily use and then after that it seemed my skin seemed to get more used to a thicker oil and absorb it better than it did. Does anyone else experience this? I'm not talking about exfoliating or irritating products that your skin has to build up tolerance towards. I'm refering to products that were too heavy or greasy for the first few uses or week or so then seemed to absorb better with the following applications. Does anyone find magic within the first bottle, pot or tube of product only have it missing in repeated purchases? Does most of the magic run out after the first application? 

Hmm interesting, I've noticed with blackhead peels, like those nose patches. The first one was absolutely amazing and pulled out so much gunk but now I have to wait a good couple weeks between each peel to get a satisfying result. The loreal dry shampoo from the clay range is actually growing on me. I didn't like it when I was trying it for the trial, but after leaving it in the back of my cupboard for ages I tried it again a few days ago (my beloved dry shampoo ran out) and wow it worked 100x better! No idea what happened but I'll continue experimenting.

Sadly I experience this all the time, drives me absolutely bonkers.  The products that seem to work for me at first are the Lush Shampoo Bars, fantastic for the first few uses, I rave about them, get a few people hooked and then it just stops working arggggh.  Then I'm back to square one and have to start the search all over again.

Maybe it is my hair becoming immune, I always knew I had awkward skin and hair but sometimes it gets a bit ridiculous.

For me it is the Timeless Vitamin C with Ferulic Acid.  Only recently have I found that after perhaps the first week the initial results go downhill and my skin begins to go red and patchy.  

The reason I found this out is because I started using The Ordinary Vitamin C again and my skin has gone back to how it was before.  I am really loving the Vitamin C 30% in silicone but I think I will continue to use both Suspensions.  

And more SQUEEEEEEEEEEEEEEEEEEEEE because I just looked on The Ordinary website and find they are releasing more retinol products!  

   That's very interesting Imoshen because I actually remember when I was on Beautylish looking over reviews of the different vitamin C products, one review recommended Timeless Vitamin C with Ferulic Acid over the Ordinary's vitamin C oil. I was really tempted since shipping adds up to the price I decided to try the other Ordinary vitamin C alternatives first.  
   And I was looking on the Ordinary's website today and there's a Resveratrol 3% + Ferulic Acid  3% which can be mixed with their Vitamin C suspensions. I'm just waiting for Beautylish to stock more stuff. 

Maybe the first few uses improve your skin but then you are not as aware as you skin has a better base than the original first uses.
I find if I use a good cream and my skin is not so dry it is then hard to see any further improvement although it does not revert back to were it was in the beginning so it is now maintaining. Just a thought ?
 

I think in some instances that is a possibility, like you said dry skin can be improved with a good serum, oil and/or moisturizer. Though somethings like pores there's always room for improvement as is seems they enlarge as the day progresses.

I used to think the little sample sachets were super potent to suck me into buying full size because they seemed so good then the full size was a let down! Lol
 

   I did wonder about that too I thought it had something to do about the product being in 100% air tight packaging and geting used up so fast. Although there was a time when I did wonder if companies did a small better batch for those sachets just get people hooked into buying the fullsized more expensive product.

You could be right with the sample as being sealed and  a small amount it doesn't expire so ingredients are at their best ?