Bird Rides and Lime, two of the leaders in the shared electric scooters space, have reduced their fundraising ambitions due to investor concerns over durability, vandalism, regulatory hurdles and heightened competition, according to a report in the Wall Street Journal.

Bird is seeking funding at its current $2 billion valuation. Lime expects to raise funds at a valuation of between $2 billion and $3 billion, down from a view of $4 billion previously.

The report details rampant vandalism, with posts on social media; scooters lasting only two months in some markets; and some cities seeking outright bans or a cap on the number of scooters. New competition includes Uber, Lyft, Ford Motor Co. and Razor USA.