i'm just playing devil's advocate here
Ethereum, Monero, and Zcash are mainstream cryptos that don't have ASICs.
These cryptocurrencies use algorithms that are designed to be ASIC resistant, but it's plausible to me that ASICs or FPGAs could be developed. However, these cryptocurrenices employ another layer of ASIC resistance: the promise of switching algorithms if ASICs are developed (or moving to proof of stake in the case of Etheruem).
This second layer of ASIC resistance is actually more important than the inherent resistance of the algorithm. I believe that it is sufficient to ward off ASIC development. The developers behind Litecoin and Dash did not implement this strategy, which is why both coins are failed projects in my book.