I think she shouldn't have invested as much on the air - but I don't think it's because her ads are ineffective. Her ads seem to be okay - but the problem is twofold:
1. People get so much of their news right away now that ads are losing effectiveness
2. Trump makes up for a lack of ads by making shocking statements and thus getting just as much if not a lot more coverage than Clinton does even with her ads.
I agree with this but I say maybe maybe not. If she can now convince the public she's actually worth voting FOR. Get some positive message out - and people are so convinced (properly) Trump is a menace - perhaps the blowout many hoped for/expected will come to pass. Jury's out. I worry it's too late as people have already cemented in the anti-Hillary & Anti-Trump camp.