Please explain.
For example, I think there will be about 2500 delegates. Lets say Cruz gets 600, Paul gets 500, Bush gets 400, Rubio gets 300, Kasich gets 200, Fiorina gets 150, Carson gets 100, Graham gets 80, Huckabee gets 50, etc... There is no candidate who gets more than 50% on the first vote. In that case, another vote will be taken and electors are not held to voting for the candidate they are supposed to vote for.
In a brokered convention, Paul, Rubio, Kasich, Fiorina, Carson, Graham, Huckabee, Pataki, Jindal etc...can be "convinced" by the Republican establishment to release their delegates to vote for Bush. It may shake out differently where they all get behind a different candidate but in the end, the part leadership get a lot more control over the process.
I think they normally avoid situations like this because it introduces a bit of uncertainty which those in control would like to avoid. I think that this time though, the people are fed up. We want a real conservative and the establishment is afraid that we might actually be able to make that happen.