Why are these a few words in the paragraph with the past tense？"need,is,choose"
I believe that we all have a vision for healthcare in this country. I believe that at the end of the day when we measure our healthcare, it will not be by the diseases cured, but by the diseases prevented. It will not be by the excellence of our technologies or the sophistication of our specialists, but by how rarely we NEEDED them. And most of all, I believe that when we measure healthcare, it will be, not by what the system WAS, but by what we CHOSE it to be.

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The speaker is looking back at the past (or the past he/she imagines). Your key phrase is "at the end of the day". This is a figurative expression, by the way; not the end of a literal day.

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At the time of "measurement", we will be looking back at the finished past. Arguably, it's incorrect and he should have said "will have needed", but the past simple is a natural and more informal choice here.