Discuss the problems of comparability of revenue recognition based on the following information:

In the UK film and television industry, a range of accounting practices has been used in recognising revenue. Three examples are as follows:

Company A: This company makes documentary programmes that are sold under contract to a television broadcasting company. Company A recognises 20 per cent of revenue during the production phase and the remaining 80 per cent when the programme is delivered to the broadcaster.

Company B: This company makes advertisements for television and receives royalty payments every time the advertisement is broadcasted. Company B has been recognising revenue at the date of signing the contract for a new advertisement. From next year, it will spread the revenues evenly over the period of the licence.

Company C: This company makes quiz programmes for television. It is paid a fixed fee per programme and recognises revenue when each quiz programme is broadcasted.