Anybody, whose role require contact the client in order to gather requirements and elicit true business needs, should be able to convince the business to optimal solutions. The problem is that it is not always easy.
Business seems to want irrational things sometimes, hence PO/BA/Dev should be able to say NO. You might try to convince the customers to change theirs mind by estimating irrational things accordingly (infinity sounds like a correct estimate ;))… However, this strategy is tricky.
Despite high estimates client might still decide to do feature in “not the wisest manner” and (by the way) make you miserable by the way.
However, there is another way! Presentation will reveal the secret of art of saying no and expressing disagreement in a firm but user-friendly manner (or friendly enough to not been thrown away from window or fired).
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