"Never write down anything except what you actually completed."
I disagree.
Documenting and sharing failures is important too. It's useful to look back and analyze sources of mistakes, misjudgments and inefficiencies.
It's also important to know for the manager to know that implementing {successfulTask} was actually fast, so it would be low cost to implement it next time.
May be a language impedance mismatch rather than actual disagreement.
Everyone on both sides of review time knows that "considered the use of AngularJS" only minimally requires 10 seconds or so. So writing that down doesn't mean much. However, a completion like "implemented a helloworld class AngularJS demonstration, and determined for X,Y,Z reasons it would be inappropriate for project Q" would be totally valid.
There are also corporate culture issues, nobody here gets a bonus for stuff that doesn't work, so it might be useful to separately document that data, but...
Another corporate culture issue relates to coddling, some employers are like the mother duck with the ducklings following her and others are like the building trades. Some places promote useful career advice and training so discussing failures might lead to training, experiments, etc. On the other hand some places just don't care, much as I really don't care if my plumber doesn't like a certain brand of pipe wrench.
I disagree.
Documenting and sharing failures is important too. It's useful to look back and analyze sources of mistakes, misjudgments and inefficiencies.
It's also important to know for the manager to know that implementing {successfulTask} was actually fast, so it would be low cost to implement it next time.