Many things, but mainly - lack of progress or initiative on EVs (despite a head start at least among germans).
If they had a good product leadership, they should have already had a 200+ mile range i3 and an i5 that is already launched or close to launch by now. Instead they are still sitting on a piddly 120 mile range i3 that is too expensive and a rather confused and now long in the tooth i8.
There's clearly been a big side step in philosophy - one minute it's "Born electric... we don't want to just electrify existing platforms...", now, under Kruger, it's electrification of much more familiar models. One was a more holistic approach, the other more pragmatic. I don't disagree with either - but I think the change in direction is what makes them look bad. People seem to be expecting the automotive landscape to shift entirely within one product life-cycle, I don't think this was ever going to be the case and I'm also not sure there are really any good benchmarks for BMW's performance.
I'll defend the i3 and i8 till I'm blue in the face because I believe they absolutely nailed their respective design briefs - I will accept though, that the market reaction to them was probably a long way from where BMW thought it would be, and in both cases they could have done more to ease the public acceptance of the models. The market wants to boil everything down to range, yet the market doesn't seem to know what range it wants... they just go with bigger is better. BMW knew before they launched the i3 what people needed from a city car.. or MegaCityVehicle, they got the data from the ActiveE and MiniE programs... where they messed up is thinking that people would be sensible out it... people want 200+ miles range... they average less than 9 miles per trip...
At the end of the day though, you have to question whether or not trying to win the race to drive down profits, in order to gain market share in quite a small market, that actually undermines your existing, proven and profitable business would really be better management. I'm not saying its a journey that the manufacturers shouldn't take... but it was only 5 years ago I stood in the Park Lane showroom marvelling at the i8 and i3 concepts, these products haven't even had a true LCI yet --- I think things are already moving fast enough.