One way to maintain timing between transmitting and receiving devices is to employ an asynchronous protocol such as start-stop.
Another cause is "losing count", as on a hard drive: if a hard drive encounters a long string of 0s, without any 1s (or a string of 1s without 0s), it may lose track of the frame between fields, and suffer bit slip.
[1][2] Thus one prevents long strings without change via such devices as run length limited codes.
Many communication systems use linear-feedback shift register scrambling to prevent long strings of 0s (or other symbol), including VSAT,[1] 1000BASE-T, RFC 2615, etc.
A bit-slip error when using any other block cipher mode of operation generally results in complete corruption of the rest of the message.