A rental contract for an indefinite period in the Netherlands is also called
Model A. It often implies a 1 year period for mutual ‘getting-to-know’ and then continues for an indefinite period.
A typical figure of a landlord that is interested in concluding an indefinite rental contract is an owner of several premises or a real-estate investor. They are not supposed to use accommodations for personal purposes. This landlord is willing to have a stable rental income and is unlikely to be the first to wish for termination of the contract.
For a landlord, termination of the agreement is possible only with substantial legal reasons - like when the tenant doesn’t pay, causes nuisance to the neighbors, and so on. A tenant, in turn, can terminate the contract after the end of the initial fixed period. S/he should inform the landlord per calendar month.