Positive input comes before Negative input (correction)

"Learners have two kinds of linguistic information at their disposal. The first is known as positive eveidence and refers to that limited set of (generally) well-formed utterances to which learners are exposed. The second, negative evidence, consist of information provided to a learner that her or his utterance is deviant in some way." p.346 of Second Language Acquisition - Gass, Selinker

Without first positive input ie. the ideal form, there is nothing to target, therefore no target form to acquire. Negative input can only come after one has first heard a target form to attempt.
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