In many cases, I am specifically saving up for or researching things, so surprise gifts might be wonderful if you're lucky. However, because the research is intimate, I might also be terribly offended at having my little personal quest dashed. I hate surprises and I hate gifts. Surprises are stressful as hell because sometimes their intention is good but their delivery is not. Gifts carry the weight of responsibility (see also Animism).
Instead of a gift of the completion of a task, I would much appreciate the gift of research or help on its completion: Advice.