Why are employees more eager to complete work in their notice periods?

[honeybee]

but reluctant to do the same work when they are on the payroll?

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[Hack]

Notice periods?

[SJWhiteley]

You are almost always remembered by your last act, coupled with not burning your bridges. You can be the most philanthropic person your whole life, but if you kick a dog just before you kick the bucket, then 'dog kicker' will be on your gravestone. Conversely, the most inconsiderate a-hole can create some redemption by being nice, placating and cooperative, in the last few days of knowing them.

Someone who switches to being 'productive' in the wee hours, tends to imply they were knowingly unproductive previously?

Other reasons? Procrastination - we are all procrastinators to some extent, so when the deadline looms, we hurry to get things done, even if that deadline is imposed by a shift to 'pursue other ventures'.

[honeybee]

I think over here it's driven more by the prospect of getting (or not getting) a "relieving letter" from the current organization which proclaims you have discharged all your outstanding duties (not necessarily in an outstanding fashion).

That's one more motivating factor I need to add to the long list of motivators. Or catalysts.

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