user30668: Let's say a lightning node A wants to route a payment to a lightning node B, being A and B not directly connected.A looks for routes throughout the network, using the info about the total capacity of available channels and construct n possible routes to reach B.
Will A just try routes until eventually one of the n succeeds? 
For what I've got by checking the BOLTS, the actual state of each sides of the channels is not announced (is it?), what means that even though a route could have enough capacity to route a payment, one of the channel could be unbalanced and the whole route may fail. Therefore, the potential failure rate when trying to route payments seems quite high.
Am I missing something?

user3041: Indeed, the current state of the channels is not announced (it is allegedly hidden for privacy purposes). Therefore, A does not know if a route has enough capacity until he tries to make the payment throught that route.
A recent study claims that success rate is around 80% for USD 1.2, but only about 1% for transactions larger than 200 USD.
Related question: In lightning network, is the balance publicly anounced in realtime?

30668: <p>Let's say a lightning node <code>A</code> wants to route a payment to a lightning node <code>B</code>, being <code>A</code> and <code>B</code> not directly connected.<code>A</code> looks for routes throughout the network, using the info about the total capacity of available channels and construct <code>n</code> possible routes to reach <code>B</code>.</p>

<p>Will <code>A</code> just try routes until eventually one of the <code>n</code> succeeds? </p>

<p>For what I've got by checking the <a href="https://github.com/lightningnetwork/lightning-rfc" rel="nofollow noreferrer">BOLTS</a>, the actual state of each sides of the channels is not announced (is it?), what means that even though a route could have enough capacity to route a payment, one of the channel could be unbalanced and the whole route may fail. Therefore, the potential failure rate when trying to route payments seems quite high.</p>

<p>Am I missing something?</p>
 3041: <p>Indeed, the current state of the channels is not announced (it is allegedly hidden for privacy purposes). Therefore, <code>A</code> does not know if a route has enough capacity until he tries to make the payment throught that route.</p>

<p>A <a href="https://diar.co/volume-2-issue-25/" rel="nofollow noreferrer">recent study</a> claims that success rate is around 80% for USD 1.2, but only about 1% for transactions larger than 200 USD.</p>

<p>Related question: <a href="https://bitcoin.stackexchange.com/questions/80130/in-lightning-network-is-the-balance-publicly-anounced-in-realtime">In lightning network, is the balance publicly anounced in realtime?</a></p>
