Well, the performance of Bitcoin was actually impressive so far, according to
https://coinmarketcap.com/currencies/bitcoin/ it was 8688$ which is very closed to 10, 000$ each bitcoin. I think once it reach that amount, it will hard for the bitcoin holders to accumulate it, because its getting expensive now. So as long as not reaching 10k$ better to buy em now then hold.
Yes, you are right because once the price of Bitcoin is kept increasing it is very hard to accumulate, in the same way, once it crosses the value of $10k then we will see the rally of altcoin which most of the Bitcoins will start pumping the potential altcoins in the market.