I think it is becoming very clear that there are way too many people investing in Lego on the whole at the moment. Even when you think you should have a winner there are just so many people willing to undercut as they need the money at that time or whatever else (maybe some people have access to free shipping etc). The stock that you have from before the media exposure of Lego investing is probably good to go in some/many cases, but afterwards, I think you're/we're struggling a bit on the whole. I've seen it mentioned many times that there are still wins to be had, and that's true, but on the whole it must be getting to the stage of people wondering what is the point of the effort of buying, storing, selling, posting for lower rewards or none at all. I was looking at the prices of Disney Minifig full sets earlier on Ebay and some dude in Germany was selling something like 80 sets at £7 lower than everyone else shipped into the UK (compared with UK internal prices). That wouldn't be too bad if the person was just selling a few and then the market could get on with it, but it will take absolutely ages to get to a point where the market starts adjusting upwards.
I'll admit that due to my love of Lego as a child I noticed the article about 'Better than Gold' at the end of 2015 or whenever it was, so I admit that I am part of the problem to some extent. However, I'm not envisaging being in a position where I would be going lower than the lowest asking price on internet sites. Doing that is the main problem for everyone else involved. I work full-time and live quite happily with my parents so have a good expendable income each month which I have been putting into many sets for the last 10 months or so. It's comfortably within my budget and I still have room in storage. I don't NEED to sell anything and I'm prepared to wait a while to see how things go. The only things I've sold so far are easy quick flips like AntMan sets picked up at RRP several months ago and other sets and minifigs/mixels reduced to ridiculous prices in-store at supermarkets. I've done well on that front. I've got around 11k of stock at the moment at RRP, but I've paid a lot less than that as I've used the advice to wait for promo's etc.
I would probably be a good case study for you guys to show what an average new brickpicker since late 2015 looks like. I can't do it tonight as I have to be up early tomorrow, but I could share a list of the sets I've picked up and the prices paid. Obviously, most of the sets I've bought are still awaiting retirement but the signs I've seen in the last few months and the amount of other sellers is slightly alarming. I can hold on to my stuff for as long as it takes (as I really do see the bul of my stuff as investment firstly), but I'd be worried if I was spending money I couldn't afford to and hoping to see a lot of profit from it in the near future. There are too many people at this at the moment.
That's not to say that there isn't money to be made now and in the future (sure there is), it's all about playing your cards right I suppose. I'm just wondering if it's worth it for most people at the moment.