Wago lever nuts vs wire nuts: what the electricians in my family argue about

Wire nuts are cheap and reliable when done right: strip 5/8", hold the wires even, twist the nut until the wires twist together outside the nut, tug test. Done wrong (not twisted enough, mixed stranded and solid without pre-twisting) they are the loose connections behind a lot of arc faults.

Wago 221 lever connectors are foolproof for mixed solid/stranded, reusable, take less box space, and are code-listed. They cost 10× more per connection. I use Wagos for anything with stranded fixture leads and wire nuts for solid-to-solid in bulk.

Either way: box fill limits still apply, and every splice lives in an accessible box with a cover.