Answer:
The contractor was wrong about his beliefs of technology and then he misguided Bob.
Step-by-step explanation:
The first factor why the contractor was wrong is because he believes that robots are not going to perform jobs like cleaning recreational harbors. Well, no one thought cellphones could make payments for you in an instant to all kinds off digital businesses and they do. Technology is limitless and that is the reason it is so valuable.
The second factor that made the contractor's opinion wrong was that he believes that robots have difficulty working underwater. In this case, he clearly doesn't know there are waterproof cellphones. and I put them as an example because they use many of the materials underwater robots could use. Like: cameras, lithium battery, GPS, microphone, receptions, and transmitters.
If the contractor knew something about technology is that it is always improving itself as he should do.