[twohlix_]

Because they can get more money faster by selling the mining units. Mining is not a guaranteed return but selling a unit is. Plus large scale mining requires a large capital risk (electricity), that is compounded with the large capital investment into the hardware.

Plus if they have significant BTC reserves (I believe they do) then selling mining equipment strengthens the BTC network and improves the value, maybe, of their current holdings.

[usrusr]

This is even more interesting than I thought at first glance: by selling hardware to other miners (for conventional money, I suppose, as that's what they need to pay upstream suppliers like TSMC) they can fund large mining power bills without having to sell their cryptotokens to do so, which would depress the market, which would threaten their whole business. BTC will crash whenever the influx of money into the network is lower than the outflux to power suppliers. Miners can't "hodl" everything when they have power bills to pay. Selling chips to mining investors is a form of inviting new money into the network.