subgrade

Apart from what others have mentioned about the usefulness of front lights, they also make you better seen to the drivers who are going to pull out in front of you from side roads and driveways. I have had a couple close calls this way.
In the dark, side visibilty is important too.

Clyde1820

Yes, for me. Mostly due to general visibility, given the roads/traffic I cope with, but also due to being less-capable of easily surviving impacts and falls as I get older.

And so, I always use a hi-viz jersey or vest, a couple of bright flashing taillight, and good bright headlights (flashing, if daytime).

Example of visibility where I ride: Today, I saw two cyclists ahead of me at about ~500yds distance. They were in line, the rearmost bike had no taillight, and the bike in front had the brightest flashing taillight I'd ever seen. At times, the rear bike completely blocked my view of the bike in front, at which point I could no longer make out the pair of bikes at that spot in the road since they blended in perfectly with the surrounding terrain. But each time the front bike with its flashing taillight was visible again, it was obvious bikes were there. All at ~500yds. A similar improvement (on the roads I use) comes when I see cyclists with very bright hi-viz gear. By comparison, it's typical on these roads for bikes without hi-viz and any taillights to blend in so completely that I often do not pick them out visually until 100yds distant; even less, around the dusk and dawn, or at "strange lighting" times.