There are many e-liquids that have been bad, or maybe just not for me. I never enjoyed smoking, so tobacco flavors are among the worst for me. Just not pleasurable at all. Like others have said, I love chocolate and I love coffee, but I haven't found a chocolate or coffee, or combination that tasted anything like either. All have been quite nasty.
But I'd have to say that the worst were in a 5-Pack DIY Sampler of Concentrated Flavorings I bought recently from Nude Nicotine. I haven't tried all 5 yet, but Banana Creme Pie and Mayan Mocha tasted pretty good on the very first puff, then after that, they left a feeling of something granulated in my throat that made me cough. And after the first puff, the flavor was gone, or at least reduced so much that all it did was make the 100% VG taste slightly better than plain 100% VG. The flavor listed on the bottle was no longer really there at all. I tried remixing with different concentrations of flavoring and dilute, but they all did the same thing. So I wrote to Nude Nicotine about it, giving details about what I had done, requested general advice, and asked two very direct questions.
While I did get a reply, I was not given any advice, and no meaningful answers to my questions. The 1st question (which to me was the most important) was totally avoided, and the 2nd told me something I had already told him I knew. So I wrote back with more questions, and stated some of the first ones differently, still trying to give details of what I had done and what I was looking for. Again, I got a two-sentence reply that did not address my questions. After four rounds of this, and my 5th PM to them, begging for answers, I did not get a reply at all. I wrote finally again saying that I had asked several direct questions that had either been totally avoided or not responded to in a meaningful way, and let them know how disappointed I was. I told him that they must not want new customers.
So this was both the worst vape, and the worst experience I have had to date. In general, our manufacturers and vendors are much more supportive. I know that MadVapes has been!!!
Thanks for the contest and another chance to win, Dude and MadVapes.
NOTE:
Many of you are not naming names, but I told Nude Nicotine that I would be warning people to stay away from them. If you've had a better experience with them, then good for you. Mine was horrible.