Part of the problem is that saying 1% sounds very arbitrary and therefore implies you have not done your research. Makes me think you just make that up and have no actual realistic plan on how to achieve it. Getting 1% of most mass markets is incredibly hard.
The real issue is that capturing 1% is the "what" but it doesn't explain the "how". You build a better "X" but 1% won't magically flow to you, otherwise there would be 100 competitors in every market with 1% each. But if you build a better "X" and you have a proven (or at least well thought out) plan to take 1% away from the dominant player in the field, then investors will like what you have to say.