Cardano is a controversial currency, some consider it to have a bright future and others find it useless.
Both versions can be supported but let's try to give an overview.

The main criticism of ADA is that it has failed to develop and attract developers to its network over many years. For the sake of transparency, Cardano's objective is to enable the development of smart contracts.
Well on this we can counter little, actually even today Cardano does not have the ability to make apps on its network, this makes it a Blockchain almost useless.
Up to this point we cannot reply.

But then what makes Cardano so attractive to investors that it is in the top 10 of the coinmarketcap?
I try to answer this way: Cardano has always had, unlike other Blockchains, a very methodological and scientific approach, moreover the development team is characterized by not insignificant experience and academic titles.
A myriad of documents and studies on the validity of the choices made by the team have been published in support of Cardano.
But let's go back to the criticism that is made, if it is true that the development team has delayed the possibility of developing smart contracts on cardano, this has happened because of the rigor and precision that is made every time a new feature is implemented. This rigour results in a product that has few bugs and has security that other networks do not have.
So the dilemma is to be first or to be best?

While it is true that the network effect in a market such as the technology one brings a not inconsiderable competitive advantage, here we are talking about infrastructures that potentially move billions, and having a bug or a problem can cause an infinite loss.
By now, the possibility of running smart contracts and creating apps on Cardano's network is just around the corner, and the market is still so immature that the network effects are not yet such that they could possibly exclude competition.
I don't see blockchain ready and able to take the whole market to date, it's still an open challenge, and perhaps Cardano is ethereum's main rival, that's what justifies Cardano's ranking.

Let the games begin!