Quantum algorithms and quantum computation

Question

Is my (very high-level) understanding correct here regarding quantum algorithms —

Quantum computers can process a massive amount of operations in parallel to the nature of qubits and their ability to have states that are superpositions of $|0\rangle$ and $|1\rangle$.

Yet when we measure the qubits all the possible states collapse into a single state of either $|0\rangle$ or $|1\rangle$, which seems to negate the potential benefits of parallel operations. All we really know are the probabilities that the states will end up as.

However, we can exploit quantum properties to increase the probability that we end up with a certain result. I believe Shor's algorithm is based on exploiting quantum properties too, although I'm not sure in what way?

e.g. in a quantum walk, quantum interference means the walk spreads faster than a classical random walk and hence can out-perform classical walks.

That is my very high level understanding of what is going on with quantum algorithms. Am I correct, 'sort-of' correct, or way-off? Can someone clarify my understanding?