What is the problem regarding the motorcyclists’ vision?

A new helmet display promises to give bikers eyes in
the back of their heads. The designer of the equipment
states that the inherent problem with motorcycles is that
the mirrors reflect a very small image and, because of
the position of the mirrors, motorcyclists mostly just see
their elbows. A small backlit display screen is added
onto motorcycle helmets with an adjustable arm which
lets riders place it just below or above their eye, in their
peripheral vision. A rear-facing camera attached to the
back of the bike streams live video via Wi-Fi to the
helmet-mounted receiver. The images are processed
and stabilised before they reach the display to
accommodate for the bike’s movements. One glance at
the display gives the rider a wide view of the road
behind them. Although the screen is just next to the
user’s face, optics fool the eye into focusing at a more
comfortable distance of around 3 metres. However, it is
still suggested that users should check their mirrors and
do the lifesaver check, turning their heads to check blind
spots