It did fail. All one needs to do is recall and post sources for these aims that PTI drew up during the events.
Remember those deadlines? And those demands? The million man tsunami that would march past all Islamabad institutions and overrun them?
The initial demands were not too unreasonable. Investigation in to the conduct of the general elections, which included, investigating NS' win, Chief Justice's role, caretaker government's role in the outcome, and supposed evidence of discrepancies and fraud. Later you asked for judicial enquiries into people named under the above who took part in the caretaker government and members of PMLN and NS' cabinet.
You also asked for electoral reform and graduation of the voting process at polling level, which as a very good demand, I fully support it.
And then the wacky part came, asking for formal resignation of Nawaz Sharif and Shahbaz Sharif, calls for government to be removed, parliament to be dissolved. Which then transpired into a weird mix of calls for re-election and threats to overthrow the government with force, come hell, high water, or police. All this you asked for at a time where Pakistan was only just looking to recover from 5 years of hell under the PPP, and at a time where revolutions in the ME had almost always lead to mass civil unrest and civil war, on-going civil war.
Now look at the above. These objectives started off somewhat reasonable and became ridiculous very fast. This entire episode of protests were orchestrated by those who wished to bring about a coup, most notable some retired generals. Though you and other common folk can't see what happens behind closed doors.
Also, to talk about the idea that IK/PTI/TuQ lost credibility and support after this is very true.
You're talking to a former PTI supporter right now, I officially quit PTI at that very time.
And I'm not alone, huge swaths of supporters quit, loyalists are too blind to use their critical thinking when it comes to their leaders.
edit: I did not know this was posted before, but to add to my argument, here's some more background: