WHY BIKE LIGHTS ARE IMPORTANT...EVEN IN DAYLIGHT
Because the statute states "every bicycle shall be equipped with a lamp" a helmet-mounted light alone would not comply with the strict interpretation of the statute. Furthermore, a red flashing taillight alone may not strictly comply with the statute either.
Based on the wording, it appears that the primary purpose of requiring bicycle lights is so that motor vehicles can see you, not necessarily so that you can see. Although the law only requires that bicycle lights be used during the defined hours of darkness, "being seen" is just as important during the day as it is at night.
While the daytime use of such lights does not help a cyclist or motorcyclist see any better, it dramatically increases the cyclist's visibility to others.
Whether you want an inexpensive daytime running light to increase your visibility or a blazing night-sun for railing singletrack at midnight, there’s a lighting system that’s made for how, where, and when you ride.
It’s important to have quality bike lights fitted if you intend on cycling after dark. It’s a legal requirement to have a white light at the front and a red and the rear, and it’s dangerous to ride without them.
Most cyclists will regularly ride after dark in the autumn and winter months, making bike lights an essential piece of kit – but it’s also considered a sensible idea to use a beam in the daytime too, to aid visibility.
WHERE AND WHEN YOU WILL USE THE LIGHTS
If you’re just commuting to work in daylight and low-light hours, a simple front and rear blinker set might suffice. If you ride after dark, a front headlight powerful enough by which to see is necessary. It might seem counterintuitive, but remember that the brighter the ambient light, the brighter the system you’ll need for visibility. Rear blinker lights that put out 15 lumens of light may seem bright after dark but are harder to see in full sunlight.