Great article. These problem statements can be improved by further defining the pain points. Being specific is important here. What qualifies as "too often" and "too far away"? What does "frustrated" mean to hosts? What exactly may they be finding "difficult"? What is "too high a rate"? Leaving these statements vague can cause you extra time as you go further into your problem solving. May I also offer another problem solving framework used by Lean Six Sigma experts:

Define. This is where you define the scope of the problem. Again, it is important to articulate your pain points as specifically as possible. You should also define what success would look like if the problem is solved. I highly recommend mapping your process at this point.

Measure. Here you will fine tune how to measure the pain in the process. You should dial in to the specifics of metrics you can gather to baseline the pain of your problem. In other words, how would you measure success? (e.g. a 5% reduction in ride cancellation)

Analyze. Next you should use tools to analyze the source of your problem. For the Lyft driver example, you would ask, "What is driving cancellations? Why are drivers too far away when requested?" You can also think of this as your diagnosis step.

Improve. Here is where you can begin defining targeted improvements in your process. What would solve the pain you are seeing? What solutions can you apply to eliminate or reduce the pain in the process? You should run a pilot of your solutions to verify they actually work before proceeding to the next step.

Control. Now that you have piloted your solutions and verified that they work, it is time to develop a solid implementation plan that also integrates a change management approach (I like using Prosci's ADKAR Model - simple but holistically effective). The goal is to walk away with an implemented process where all stakeholders are engaged in supporting the change you have created.

There are other frameworks you can use for problem-solving; there is not a one-size fits all approach. Use what works for your particular situation.