Bitcoin Cash was created because Bitcoin lacks governance. Dash has formal dispute-resolution, a treasury system, incentivized infrastructure, and more.
Dash is 3,600x faster than Bitcoin Cash.
Dash has protocol-level privacy.
Some users of Bitcoin Cash attempted to provide for privacy within the cryptocurrency, but unfortunately, the model they developed is unreliable. This is because it requires volunteers to take the initiative, as well as bear all the costs, to run privacy servers. Dash, on the other hand, has privacy available to all of its users all of the time, thanks to its 100% uptime Masternode network.
Dash's infrastructure is fully incentivized.
Bitcoin Cash relies heavily on volunteers to run its node infrastructure. This has lead to “pricing out” problems as volunteers drop off the network as the cost to run a node increases. In contrast, Dash’s infrastructure is both steady and growing due to block reward incentives paid to Masternodes.
Dash is self-funded and does not rely on donations.
Bitcoin Cash relies exclusively on volunteers and corporate sponsors to develop its codebase. This has created crises of governance for the cryptocurrency, wherein different portions of Bitcoin’s Cash’s network couldn’t agree on product fundamentals. The lack of governance eventually spawned the different versions of Bitcoin Cash that now exist (ABC and SV). Dash, however, remains a single cohesive network by making available a portion of its block reward — dubbed the “Treasury” — to be allocated by masternode approval to any development team applying for it. This accomplishes two things at once: 1) the allocated funds provide full-time support to developers, and 2) they implicitly provide governance, as the codebase vision of the approved development teams becomes the de-facto vision of the network.