The Tasks do sometimes have to be done out of order in order to accommodate observations.
Some Tasks can be done ahead of time as part of the preparation for the lab exercise.
The Tasks are NOT always the full instructions.
You need to read/work your way through the lab exercise to make sure you get the full instructions and to get the information you need to do the Tasks.
If you try to just do the Tasks without the reading lab exercise, then often you do NOT know what to do.
A few sections and Tasks are explicitly marked as "Optional at the discretion of the instructor." These sections and Tasks are the ones the lab author thinks might need to be omitted. However, the instructor is free to omit sections and Tasks as they find necessary.
In fact, the lab exercises are all designed to be complete explorations of their main themes, and therefore usually are a bit too long intentionally. Also some sections/tasks might be too difficult for some classes. So some omissions are almost always necessary. The instructor should NOT as a usual rule shorten the lab below about 2 hours (see Lab Duration).
That learning is what helps you in following courses and all the rest of your life.
That said, to get an acceptable/good/great grade complete the Report Form correctly, completely, neatly.